句子是表达思想的基本单位,句子由单词组成,但组成时必须遵循一定的规则,这就是语法。违反了这些规则,语言就不正确,也就不能正确地表达思想,因此每句话都牵涉到语法。就书面语而言,每句话第一个字母必须大写,句末必须有句号,如果是问句,末尾应加问号,如:
We are learning English.
Who is your teacher?
① 句子总的说来由两部分构成,即主语(subject)与谓语(predicate),如:
② 这里讲的谓语是指广义的谓语,通常说谓语是指动词或动词短语,后面常可跟(一个)宾语(object)或状语(adverbial),如:
① 呼语(vocative),指对听话人的称呼,如:
Good morning, Tom .
② 同位语(appositive),加在一个名词后面,说明它指谁或指什么事物,如:
She was born in Berkeley, a small town in California .
③ 插入语(parenthesis),指在一句话中插进去的成分,如:
This, I think , is the best way to help them.
上面三种成分常用逗号把它们和句子的其他部分分开。
句子按说话目的可以分为四类:
I wish you success. (愿望)
He may be in bed now. (猜测)
May I ask you a question?
Where should I sit?
Get everything ready tomorrow. (命令)
Take care! (叮嘱)
How beautiful (this is)!
How silly (you are)!
问句主要分为四类:
Are you from Japan? —Yes, I am.
Do you like horror films? —No, I don't.
Who is it on the phone?
Where have you been?
Are you from the South or from the North?
Is he going by train or by plane?
① 这种问句由两部分组成,前面部分是一个陈述句,后面部分为一简短问句(称为question tag),如:
This is your car, isn't it?
They are your children, aren't they?
② 要注意,如果前面部分是肯定句,后面的简短问句一般要用否定形式(上面例句都是这样的)。反之,如果前面部分为否定句,则后面的简短问句要用肯定形式,如:
You don't like rock music, do you?
Your wife isn't in China now, is she?
③ 在个别情况下,前后两部分可以都是肯定或都是否定。这时有特殊的含义,如:
So he won't pay his bills, won't he? We'll see about that.(=He is too naive to think.) (有威胁的意思。)
You sold that lovely bracelet, did you? (=I'm sorry you did.) (真遗憾。)
词在构成句子时有一定的顺序,肯定句通常按下列顺序排列:
谓语有时全部或部分地提到主语前面时,称为倒装语序。问句很多都用倒装语序: