Chọn C
Câu đề bài: “Mặc dù sấm và sét được tạo ra cùng một lúc, sóng ánh sáng đi xa hơn___________, vì vậy chúng ta thấy sét trước khi chúng ta nghe thấy sấm ".
Đáp án C: than sound waves do
—» Đây là cách nói rút gọn của “than sound waves travel”: cấu trúc so sánh hơn kém:
S + V + trạng từ ngắn đuôi er/dài thêm more + than + S + V.
* Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Although thunder and lightning are produced at the same time, light waves travel faster________, so we see the lightning before we hear the thunder.
A. do sound waves
B. than sound waves are
C. than sound waves do
D. sound waves
Although thunder and lightning are produced at the same time, light waves travel faster _______, so we see the lightening before we hear the thunder
A. than sound waves do
B. than sound waves are
C. do sound waves
D. sound waves
Mark the letter A, B, C or D to indicate the correct answer to each of the following questions.
Question 8: Although thunder and lightning are produced at the same time, light waves travel faster _____, so we see the lightening before we hear the thunder.
A. than sound waves do
B. than sound waves are
C. do sound waves
D. sound waves
Although thunder and lightening are produced at the same time, light waves travel faster _____, so we see the lightening before we hear thunder.
A. the same as sound waves
B. than sound waves are
C. than sound waves seem
D. than do sound waves
Read the passage and choose the best answer.
A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms.
Which type of waves does radar use?
A. tidal
B. sound
C. heat
D. radio
Read the passage and choose the best answer.
A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms.
According to the passage, the distance between a radar set and an object can be determined by _______.
A. the time it takes for a burst of radio waves to produce echoes when the waves bounce off the object
B. the term “ranging” used for detection of the distance between an object and the radar set
C. the time it takes for the radio waves to produce echoes and bounce off the object
D. the time it takes for the echoes produced by the radio waves to return to the radar set
Read the passage and choose the best answer.
A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms.
Which of the following would most likely be the topic of the next paragraph?
A. A history of flying.
B. Other uses of radar.
C. The technology used by pilots.
D. Uses of some technology.
Read the passage and choose the best answer.
A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms.
The word “shouts” in the passage most closely means _______.
A. “exclaims”
B. “yells”
C. “shoots”
D. “whispers”
Read the passage and choose the best answer.
A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms.
The word “exemplified” in the passage can be replaced by _______.
A. “specified”
B. “resembled”
C. “illustrated”
D. “justified”
