1. 并列結(jié)構(gòu)中,and用于肯定句,or通常用于否定句表示“和,與”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 表轉(zhuǎn)折。
2. or用在選擇疑問句中,意為“或者,還是”。例如:
Is he a doctor or a teacher? 他是醫(yī)生還是教師?
Did you do your homework or watch TV last night?你昨晚做作業(yè)還是看電視了?
Are they singing or reading English? 他們是在唱歌還是在讀英語?
3. or在句型“祈使句+or+陳述句”中,表示在以祈使句為條件下的相反假設(shè),or意為“否則,要不然”。例如:
Work hard,or you will fall behind.你要努力學(xué)習(xí),否則會落后。
I must work hard, or I'll fail in the exam. 我要努力學(xué)習(xí),否則考試要不及格了。
4. either…or 意思為"或者……或者……"。注意謂語動詞的主謂一致采用就近原則。例如:
Either you or I am right. 不是你對,就是我對。
5. or在“either…or…”結(jié)構(gòu)中,意為“要么……要么……”。連結(jié)的并列成份可在句中作主語、表語、謂語、賓語等。例如:
Either she or I am right.不是她對就是我對。(連接主語)
The shoes in the shop were either too big or too small for me. 店里的鞋對我來說不是太大就是太小(連接表語)
He either does his homework or watches TV on Sundays.他星期天要么做作業(yè),要么看電視。(連接謂語)
We play either football or basketball in the afternoon.下午我們不是踢足球就是打籃球。(連接賓語)
6. or表示不確切、模糊的陳述。例如:
This story happened five or six years ago. 這個故事發(fā)生在四、五年前。
Is the street straight? More or less. 這棵樹直嗎?差不多。
She will find that she was wrong sooner or later.她遲早會發(fā)現(xiàn)她是錯的