[单项选择]The scientist will give us a talk ______ the moon.


A. for
B. in
C. on

[单项选择]The scientist will give us a talk ______ the moon.


A. for
B. in
C. on

[单项选择]A scientist will come to give us a talk ______ computer.


A. at
B. on
C. of

[单项选择]What does the talk tell us

[单项选择]Unless you give us a satisfactory explanation about quality, we will have no choice but to reject your goods.（）
A. 除非你方能在质量方面给一个满意的答复，否则我们将不再选择，而是拒绝你方的货物。
B. 除非你方能就质量问题给一个满意的解释，否则我们只能拒绝你方的货物。
C. 只要你们的解释能让我们满意货物的质量，我们就不会拒绝你们的货物。
D. 只要你们的解释不能让我们满意，还存在质量问题，我们将拒绝你们的货物。

[单项选择]She had a strong （） to give a talk about her experiences, because she didn't like the limelight.
A. disinclination
B. dissolution
C. dissidence
D. dissension

[单项选择]

Sparks created in a lab give off X-rays, scientists announced Monday.
X-rays are a byproduct (副产物) of high-energy electron discharges in the Sun, in exploding stars, and even in lightning. Many scientists did not expect sparks alone to do the trick.
Researchers at Florida Institute of Technology brought their equipment, which had detected X-rays in lightning, into the lab. Half the team expected to see X-rays and the other half did not.
In sparks of 1.5 million to 2 million volts, the researchers indeed recorded X-rays that were remarkably similar to those produced by lightning.
"This amazed us, It opens the door to answering really big questions about lightning by generating it in the lab," said team member Hamid Rassoul. "It also tells us that we have a lot’ to learn about how even small sparks work."
X-rays are a form of electromagnetic radiation, on a spectrum (频谱) that runs from radio waves on the low
A. Scientists Created X-rays in a Lab.
B. Sparks, a New Way to Produce X-rays.
C. Runaway Breakdown Triggers New Questions.
D. Scientists Surprised by X-rays from Lab Lightning.