连词and和or用法区别
and和or是初中英语的常见并列连词,用于引导两个并列的词、词组或句子。and的基本意思是“和,与”,or的基本意思是“或者,还是”。它们的用法区别如下:
1. 并列结构中,and用于肯定句,or通常用于否定句表示“和,与”之意。
There are some students and teachers on the playground.
There is no air or water in the moon.
---I don’t like chicken ___ fish.
---I don’t like chicken, ___ I like fish very much.
A. and; and B. and; but C. or; but D. or;and
答案C。否定句中表并列用or, but 表转折。
2. or用在选择疑问句中,意为“或者,还是”。
例如:
Is he a doctor or a teacher? 他是医生还是教师?
Did you do your homework or watch TV last night?你昨晚做作业还是看电视了?
Are they singing or reading English? 他们是在唱歌还是在读英语?
3. or在句型“祈使句+or+陈述句”中,表示在以祈使句为条件下的相反假设,or意为“否则,要不然”。
例如:
Work hard,or you will fall behind.你要努力学习,否则会落后。
I must work hard, or I'll fail in the exam. 我要努力学习,否则考试要不及格了。
4. either…or 意思为"或者……或者……"。注意谓语动词的主谓一致采用就近原则。
例如:
Either you or I am right. 不是你对,就是我对。
5. or在“either…or…”结构中,意为“要么……要么……”。连结的并列成份可在句中作主语、表语、谓语、宾语等。
例如:
Either she or I am right.不是她对就是我对。(连接主语)
The shoes in the shop were either too big or too small for me. 店里的鞋对我来说不是太大就是太小(连接表语)
He either does his homework or watches TV on Sundays.他星期天要么做作业,要么看电视。(连接谓语)
We play either football or basketball in the afternoon.下午我们不是踢足球就是打篮球。(连接宾语)
6. or表示不确切、模糊的陈述。
例如:
This story happened five or six years ago. 这个故事发生在四、五年前。
Is the street straight? More or less. 这棵树直吗?差不多。
She will find that she was wrong sooner or later.她迟早会发现她是错的。