影响化学毒物简单扩散的因素是A．分子量B．脂溶性C．离子通道D．能量E．载体

Many teenagers feel that the most important people in their lives are their friends. They believe that their family members, especially their parents, don’t know them as well as their friends do. In a large family, it is quite often for brothers and sisters to fight with each other and then they only go to their friends for getting ideas.

It is very important for teenagers to have one good friend or a circle of friends. Even when they are not with their friends, they usually spend a lot of time talking among them on the phone. This communication is very important in children’s growing up, because they can not discuss something difficult to their family members.

Parents often try to choose their children’s friends for them.Some parents may even stop their children from meeting their good friends: The question of “choice” is an interesting one. Have you ever thought of the following questions?

    Who choose your friends?

Do you choose your friend or your friends choose you?

Have you got a good friend your parents don’t like?

Your answers are welcome.

小题1:Who know them better than their parents for the teenagers?

A．Their parents.

B．Their friends.

C．Brothers and sisters.

D．Family members.小题2:How do they communicate when the teenagers stay alone?

A．Go to their friends.

B．Talk with their parents:

C．Talk with their friends on the phone.

D．Have a discussion with their family by phone.小题3:Which of the following sentences is true?

A．Parents should like everything their children enjoy.

B．In all families, children can choose everything they like.

C．Teenagers can only go to their friends for help.

D．Parents should try their best to understand their children better.小题4:What is the meaning for “Your answers are welcome. ”?

A．You are welcome to have a discussion with us.

B．You have got an idea, so your answers are welcome.

C．Your answers are always right.

D．You can give us all the right answers.小题5:. Which is the best title of this passage?

A．Only parents can decide.

B．Parents and children.

C．A strange question.

D．Teenagers need friends.

百万位的右边是千万位。[ ]

圆心到圆上任意一点的线段叫半径。[ ]

会议决定，《城市生活无着的流浪乞讨人员救助管理办法(草案)》经进一步修改后，由国务院公布______，同时______1982年5月国务院发布的《城市流浪乞讨人员收容遣送办法》。

填入划横线部分最恰当的一项是( )。

A．实行废除
B．施行废止
C．实行废止
D．施行废除

单轨吊制动闸原理可简单概括为液压开闸，（）制动。