单项选择题

Questions 17 to 20 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions. Now listen to the passage Whether there is sufficient nitrogen on Mars is important because it_________.

A．can raise the temperature of Mars
B．can protect living beings from harmful rays
C．can change the atmosphere of Mars
D．is an important part of the air people breathe

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单项选择题

What do we infer from the conversation

A．Joe will never get used to using checks.
B．Joe will pay his telephone bill by money order.
C．Joe will not have a lot of cash on himself.
D．Joe will open a deposit account.

单项选择题

How many people got injured in the attack against the police station

A．1
B．2.
C．3.
D．4.

Questions 17 to 20 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions. Now listen to the passage Whether there is sufficient nitrogen on Mars is important because it_________. 您的浏览器不支持 audio 元素。

Questions 17 to 20 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions. Now listen to the passage Whether there is sufficient nitrogen on Mars is important because it_________.