文档介绍：肯定句变否定句
am a student. →
I am not a student.
are sad. →
You are not sad.
3. She is a good girl. →
She is not a good girl.
was Monday. →
Yesterday was not Monday.
were busy yesterday. →
They were not busy yesterday
（ is, am , are, was, were),就在be动词后面直接加not。
be 动词和not的缩写形式：
is not = isn't
are not = aren't
was not = wasn't
were not = weren't
注意：am not 不能缩写。
1. He is a boy.
He is not a boy.
2. I am your friend.
I am not your friend.
3. My sister is a beautiful girl.
My sister is not a beautiful girl.
are some books on the bookshelf.
There are not any books on the bookshelf.
5. I was at home yesterday.
I was not at home yesterday.
6. They were in Beijing ten years ago.
They were not in Beijing ten years ago.
注意：句中有some,一般要改为any.
can swim. →
I can not swim.
will go to the park. →
You will not go to the park.
3. Peter need go home now.
Peter need not go home now
4. You should open your book.
You should not open your book.
5. He must finish his homework.
He must not finish his homework.
（can ,may, must, should ,need, will等），就在这些单词后面直接加not。
can not = can't
must not = mustn't
should not = shouldn't
need not = needn't
will not = won't
1. Lucy will be back in