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Although most universities in the United States are on a semester system, which offers classes in the fall and spring, some schools observe a quarter system comprised of fall, winter, spring, and summer quarters. The academic year, September to June, is divided into three quarters of eleven weeks each beginning in September, January, and March: the summer quarter, June to August, is composed of shorter sessions of vary length.
There are several advantages and disadvantages to the quarter system. On the plus side, students who wish to complete their degrees in less than the customary four years may take advantage of the opportunity to study year round by enrolling in all four quarters. In addition, although most students begin their programs in the fall quarter, they may enter at the beginning of any other quarters. Finally, since the physical facilities are kept in operation year round, the resources are used effectively to serve the greatest number of students. But there are several disadvantages as well. Many faculties complain that eleven- week term is simply not enough for them to cover the material required by most college courses. Students also find it difficult to complete the assignments in such a short period of time.
In order to combine the advantages of the quarter system with those of the semester system some colleges and universities have instituted a three-term trimester system. In fourteen weeks, faculty and students have more time to cover material and finish course requirements, but the additional term provides options for admission during the year and accelerates the degree programs for those students who wish to graduate early.
He was very angry because he couldn’t find the report ___ .
You look pale. You ___ too hard these days.
It was so warm that we ___ wear our coats. It was very pleasant.
___ ___he would have signed his name in the corner.
It was ___ music I have ever heard.
Please, tell me something ___ than this old joke.
I don’t like maths. I don’t like science, ______.
It is expected that man ______ on several planets by the end of this century.
They have got enough money ___ to the cinema.
The girl ___ in the yard asked me the time
He is _____ that he has no time for regular meals.
He has been very lonely since _____ .
You may find the end of the story quite _____ .
Today many parents ________ their children go to bed late.
Jane is the same age ________ Mary.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
When we feel anxious, we often give ourselves negative messages like: “I can’t do this”, “I’m useless” and “I’m going to fail”.
It can be difficult but (16) to replace these with positive thoughts such as: ‘this is just anxiety, it can’t harm me’ and, ‘relax, concentrate - it’s going to be okay’.
Picturing how you’d like things to go can help you feel more (17) ____. Try to imagine yourself (18) up to an exam feeling confident and relaxed. You turn over your paper,write down what you do know and come away knowing you tried your best on the day.
It can sometimes feel like your whole future depends on (19) grades you get. There can be a lot of pressure (20) young people to do well in exams which cancause a lot of stress and anxiety. You might have (21) certain grades or put into ahigher set, and feel if you don’t get the grade you’ll let your teachers or parents (22) ____.
Remember, exams are important – but they’re not the only way to a successful future. Lots of people (23) success in life without doing well in school exams.
Choose the word (A, B, C or D) that best fits the blank space.
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
What is the main idea of the passage?The original atmosphere on Earth was unstable.
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
The word "enveloped" in the second paragraph is closest in meaning to ____
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
According to the passage, out gassing eventually led to all of the following EXCEPT:
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
The word "they” in the second paragraph refers to
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
The passage suggests that oxygen remained in the atmosphere because ___
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
The word "At any rate" in the fifth paragraph is closest in meaning to
The atmosphere that originally surrounded Earth was probably much different from the air we breathe today. Earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium--.the two most abundant gasses found in the universe--as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the Earth's hot surface.
A second, more dense atmosphere, however, gradually enveloped Earth as gasses from molten rocks within its hot interior escaped through volcanoes and steam vents. We assume that volcanoes spewed out the same gasses then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about ten percent), and up to a few percent nitrogen. These same gasses probably created Earth's second atmosphere.
As millions of years passed, the constant outpouring of gasses from the hot interior--known as out gassing
It appears that oxygen, the second most abundant gas in today's atmosphere, probably began an extremely slow increase in concentration as energetic rays from the sun split water vapor into hydrogen and oxygen during a process called photodissociation. The hydrogen, being lighter, probably rose and escaped into space, while the oxygen remained in the atmosphere.
This slow increase in oxygen may have provided enough of this gas for primitive plants to evolve, perhaps two to three billion years ago. Or the plants may have evolved in an almost oxygen-free (anaerobic) environment. At any rate, plant growth greatly enriched our atmosphere with oxygen. The reason for this enrichment is that plants, in the presence of sunlight, process carbon dioxide and water to produce oxygen.
Which of the following does the passage mention as necessary for both the production of oxygen by photodissociation and the production of oxygen by plants?