问题 问答题

生活中常用洗涤剂和汽油去除油污,请分别简要说明两者的原理.

答案

汽油清洗油污是由于油污能溶于汽油,而加了洗涤剂的水,洗涤剂具有乳化作用,能将油污乳化,而易于洗涤,所以使用汽油和洗涤剂清洗油污的原理不同.

故答案为:汽油能溶解衣服上的油污,从而具有去油污的作用,而洗涤剂具有乳化作用,能使衣服上的油污分散成无数细小的液滴随水流走,从而具有去油污的作用.

判断题
阅读理解

    If you feel at present that you don’t have enough friends in your life,one reason may be that you have let yourself become too busy to make time for the relationships you already have.Starting and keeping friendship requires effort and commitment.

Many of us let our lives become so busy with work and other commitments that we don’t get around to scheduling time for pleasure and renewal(叙旧)with the friends,relatives and acquaintances we already have.

Making the effort to call your friends more regularly and to accept more of the invitations you receive from others can improve your social life in a hurry!

Are there any people you could call right now and be assured of a pleasant welcome? Are there people that you could count on to help you in time of difficulty? Can you have close talks with them? Do you have fun when you are together? Are you happy to have them in your life?

If you haven’t seen much of them lately。is it because you have become too busy? Have you grown apart? Was there an argument?

If the main reason you haven’t been getting together with the people you already know is that you have gotten too busy,take a good look at how you spend your time.Compare it with your real values and priorities(优先考虑的事)in life.Is your busy lifestyle really bringing you the quality of life that you want?   

If you have become too busy for friends,why has this happened? Are you seeking material toys in your life at the expense of relationships with other human beings? Have you allowed your time to be over.committed because you never say“No”to anyone? Do you insist on doing things yourself that could be delegated to others? If so,why? Do you believe that everything depends on you?

Examine whether the way you are now spending your time accurately reflects your deepest values and priorities.Make sure that you schedule enough time for the things that are truly most important to you.

If you really want to keep friends in your lire,make a space in your schedule,and a space in your heart for them.

小题1:In this passage the author mainly discusses       .

A.how to balance friendship and work

B.how to spend our spare time

C.whether we should keep friendship

D.whether we should invite friends to dinner小题2:Which of the following doesn’t indicate a good relationship?

A.You have someone to count on when you are in trouble.

B.You have someone to have close talks with.

C.You feel depressed with others in life

D.You have fun when you are with someone小题3:The underlined word“delegated”probably means“       ”.

A.appointed

B.replaced

C.declined

D.handled