问题 单项选择题

紊流可视为恒定流,是指流体的运动要素的()不随时间而变化。

A.瞬时值

B.脉动值

C.时均值

D.脉动值的最大值

答案

参考答案:C

解析:紊流可视为恒定流是指流体的运动要素的时均值不随时间而变化

阅读理解

Without mutual(相互的)respect, any relationship will be an unhappy one . People who respect each other: a) value each other’s opinions, b) listen to each other, and c) disagree without screams or insults(侮辱). And remember, your parents have lived longer than you—don’t discount their experience and knowledge.

Your parents want to know what’s going on in your life. If you don’t tell them they won’t know when you need their help or whether they can trust you. Tell them what you’re doing, share your thoughts and feelings with them, and ask for their advice for your problems( you don’t have to follow it). Communication builds closeness. Trust is your key to freedom. The way to build trust is through honesty and responsibility. Honesty means you don’t lie or manipulate(作假). Responsibility means that you are reliable(可依赖的) and make good choices to use good judgment. When your parents trust you, it’s a lot easier for them to say “Yes.”

These guidelines(指导方针) work both ways. If sometimes, your parents break any of these guidelines, talk to them about it. Pick a time when you are both calm and feeling good toward each other(never when you are angry). Then , explain to them what they did, how it makes you feel, and what you’d like them to do instead.

Unfortunately, these guidelines don’t always work. Since we can only control what we do, and not what our parents do, sometimes we just cannot change a bad relationship. If this is the case, try to use these guidelines to at least improve things a little, and talk with a trusted adult who may be able to help you

小题1:What’s the probable meaning of the underlined word” discount” in the first paragraph?

A.To think or say that something is not important or not true.

B.To disagree with somebody’s opinions.

C.To respect somebody’s opinions

D.To accept somebody suggestions.小题2:The main idea of the second paragraph is about_______

A.feelings

B.advice

C.closeness

D.communication小题3:From this passage we know that the writer may be________.

A.an editor

B.an expert

C.a doctor

D.a teacher小题4:The main purpose of the passage is_______.

A.to show that your parents want to know what’s going on in your life.

B.to discuss how to have great relationship with your parents.

C.to discuss how to talk with a trusted adult who may be able to help you

D.to discuss how to respect your parents.

单项选择题