变成否定有规则，
“是”“将”“有”后加 not。
假如没有“是”“有”“将”，
动词前面加 don't (doesn't ／ didn't) 。
【说明】
八种时态由陈述句变成否定句，陈述句中谓语含有助动词be，have (has) ，will (shall)的，就在助动词的后面加上 not，一般现
在时与一般过去时谓语动词不含助动词，则在动词前面加上don't，doesn't，didn't。如：
①They are studying English now. →They are not studying Eng-lish now.
②They study English. →They don't study English.
( 参见“部分否定句与全部否定简介”和“肯定句变否定句应注意的问题”二文 )
Exercise：
将下列句子变为否定句。
1． There are some pictures on the front wall．
2． He has written his composition already．
3． They always go to work early in the morning．
4． Both of them are good students．
5． All of the students are fourteen years old．
6． Everyone has been to Beijing twice．
7． The English child can read and write in Chinese．
8． We'll go with him，too．
9． Open the window，please．
10．Let's go out for a walk．
11．I think he'll be here soon．
12．Both Jack and Tom are from England．
13．You'd better come here earlier next time．
14．I must hand in my homework now．
Key：1． There aren't any pictures on the front wall．
2． He hasn't written his composition yet．
3． They never go to work early in the morning．
4． Neither of them is good students．
5． None of the students are fourteen years old．
6． No one has been to Beijing twice．
7． The English child can't read or write in Chinese．
8． We won't go with him，either．
9． Don't open the window，please．
10．Let's not go out for a walk．Don't let us go out for a walk．
11．I don't think he'll be here soon．
12．Neither Jack nor Tom is from England．
13．You'd better not come here earlier next time．
14．I needn't hand in my homework now．
,
