Theory must be based on practice. 理论必须以实践为基础。

The people in the south live on rice. 南方人主食大米。(靠)

The citizens live on their salaries. 城市人靠薪金生活。

You can"t afford luxuries, on an income of 100 yuan a month． 靠月薪100元的收入，你是买不起奢侈品的。

Her pet dogs were fed on the choicest food． 她用精饲料喂养她心爱的狗。

He is just a scrounger, who lives on other people. 他正是一个小偷，专靠损害别人过日子。

Keep the kettle on the boil (=boiling). 让水壶的水一直开着。

The enemy are on the run (=running). 敌人在逃跑。

介词(preposition)：也叫前置词。在英语里，它的搭配能力最强。但不能单独做句子成分需和名词或代词（或相当于名词的其他词类、短语及从句）构成介词短语，才能在句中充当成分。

介词的种类：

（1）简单介词：about, across, after, against, among, around, at, before, behind, below, beside, but, by, down, during, for, from, in, of, on, over, near, round, since, to, under, up, with等等。

（2）合成介词：inside, into, outside, throughout, upon, without, within

（3）短语介词：according to, along with, apart from, because of, in front of, in spite of, instead of, owing to, up to, with reguard to

（4）分词介词：considering, reguarding, including, concerning

介词短语：

构成 例句

介词+名词 We go to school from Monday to Saturday.

介词+代词 Could you look for it instead of me?

介词+动名词 He insisted on staying home.

介词+连接代/副词 I was thinking of how we could get there.

介词+不定式/从句 He gives us some advice on how to finish it.

介词的用法：

一、介词to的常见用法

1.动词+to

a)动词+ to

adjust to适应,

attend to处理；照料,

agree to赞同,

amount to加起来达…，

belong to属于,

come to达到,

drink to为…干杯，

get to到达,

happen to发生在某人身上,

hold to紧握,

lead to通向,

listen to听,

occur to想起,

object to反对,

point to指向,

respond to回答,

refer to参考；指的是…；涉及,

reply to回答,

see to负责,

stick to坚持,

turn to求助,

write to给某人写信。

b)动词(+sth.)+to+sb.

announce to通知某人, describe to向某人描述, explain to向某人解释, express to对某人表达, mention to提及, nod to向某人点头, report to报告, say to告知, shout to对某人大叫, suggest to对某人提建议,speak to与某人交谈, talk to跟某人谈话, whisper to和某人低声耳语。

c)动词+sth./sb.+ to +sth./sb.

add to增加, compare to比作, carry to运送至, devote to致力于,introduce to介绍给, invite to邀请参加, join to连接到, leave to委托给,reduce to下降至, sentence to判处, take to带到。

2. be +形容词/过去分词+ to

be alive to觉察；晓得, be attentive to注意；留心, be awake to知晓,

be blind to缺乏眼光,

be close to紧挨着,

be common to对某人来说很普通, be contrary to违反；反对, be devoted to致力,

be deaf to不愿意听,

be equal to有…的力量, be exposed to暴露；遭受, be fair to对…公平,

be familiar to对某人来说熟悉, be grateful to对某人心存感激, be good to对…有好处, be harmful to对…有危害, be important to对…重要, be kind to友好对待,

be known to周知于,

be married to嫁给,

be moved to转移到,

be near to靠近,

be necessary to对…有必要, be opposite to在对面,

be opposed to反对,

be pleasant to合某人之意, be proper to专属,

be polite to礼貌待人,

be rude to粗暴对待,

be relative to与…有关, be strange to不习惯,

be similar to类似,

be suitable to适合,

be true to忠实,

be thankful to感激,

be useful to对…有用,

be used to习惯。

3.to+名词构成的词组