What does the phrase “clam up” in Paragraph 2 probably mean?

A．become excited

B．show respect

C．refuse to talk

D．seek help

1933年罗斯福实行新政以后，美国商品获得了更大的海外市场，国内商品价格也有一定提高，债务人特别是农民的债务负担减轻了将近一半。对这些变化起直接作用的新政措施是

A．整顿财政金融

B．调整农业结构

C．复兴工业生产

D．实行社会救济

What is the woman trying to do?

A．Finish some writing.

B．Print an article.

C．Find a newspaper,

My parents have promised to come to see me before I for Africa.

A. have left B. leave C. left D. will leave

下列关于电磁波的说法正确的是

A．均匀变化的磁场能够在空间产生电场

B．电磁波在真空和介质中传播的速度相同

C．只要有电场和磁场，就能产生电磁波

D．电磁波在同种介质中只能沿直线传播

Why did David decide to leave school and start working?

A．He received lots of job offers.

B．He was eager to help his mother.

C．He lost interest in school studies.

D．He wanted to earn his own living.