be動詞的用法
在英語語法中，be動詞意思和用法很多，一般的意思是：是，此種用法，有多種變化形式，is，am，are，was，were，being，been，to be.另外，be動詞還有成為的意思。根據(jù)句子中不同的人稱、數(shù)和時態(tài)，應(yīng)該選擇相應(yīng)的be動詞。
be (be/is/are/am/was/were)
[bi:]
vi
he is, we are, you are, they are (縮略式 I'm, you're, he's, we're, you're, they're), (否定縮略式 I'm not, isn't, aren't), 過去時 I was, you were, he was, we were, you were, they were (過去時否定縮略式 wasn't, weren't),過去分詞been,現(xiàn)在分詞being
英語的“be”是個特殊動詞;有些語言，如馬來文等，并沒有“be”這樣的動詞。
“Be”除了原形的“be”之外，還有另外七種形式：am, is, are, been, being, was, were.
在句子中，“be”可以是主動詞(The Principal Verb)或助動詞(The Auxiliary Verb)
【當(dāng)做主動詞時，“be”在性質(zhì)上屬于接系動詞(The Linking Verb), 后面要有名詞、形容詞、地方副詞或短語作補足語(The Complement)?！坷纾?/strong>
The man is a science teacher.
這個男子是一位科學(xué)教師。
Mary's new dressesare colourful.
瑪麗的新衣服色彩鮮艷。
I havebeen there before.
我以前去過那里。
My motheris in the kitchen now.
我媽媽現(xiàn)在在廚房里。
★這四個都是陳述句，可以變成疑問句，方法簡單，把主語和“be”或助動詞對換位置即可：
Is the man a science teacher?
Are Mary's new dresses colourful?
Have I been there before?
Is mother in the kitchen now?
★當(dāng)“be”要在祈使句中出現(xiàn)時，陳述句可借助助動詞“do”，否定句必須在前加上助動詞“don't”，如：
Don't be silly!
Do be obedient!
Be careful!
Don'tbe a fool!
★“Be”有兩種縮寫法，如下：
He's not...../He isn't....
You're not...../You aren't...
★但“am + not”的縮寫法只有一個：
I'm not.
有人用“ain't”, 但這并不是標(biāo)準(zhǔn)英語。
談過了“be”作主動詞的功能
【1.】“Be + 現(xiàn)在分詞”以組成進(jìn)行式時態(tài)(Continuous Tenses)，如：
Tony's maidis washing his new car.
The children are playing in the field.
Samuelwas eating when I came in.
We havebeen living here since 1959.
【2.】“事/物人 +Be + 過去分詞”以組成被動語態(tài)(The Passive Voice),如：
Her money in the drawer was stolen
A number of good jobs are taken up by foreigners
David studied in Taiwan but hasbeen trained as a language lecturer in America
Can all the wonderful birds be found in our Bird Park
The disobedient boywas told to stand out- side the classroom
Steps are being taken to reduce traffic con- gestion during peak hours
Dishonest students will be immediately dealt with