我們注意到操作詞都是動詞的現(xiàn)在式或過去式，是限定動詞形式。限定動詞形式可以并只可以用于謂語動詞詞組第一動詞的位置。也就是說操作詞在句子中的位置是謂語動詞詞組第一動詞位置。

當(dāng)一個句子按語法要求需要用操作詞而原句沒有操作詞時，就在謂語動詞詞組第一動詞位置加上助動詞do的現(xiàn)在式或過去式，使其具有操作詞。助動詞do后接原實意動詞的不帶to的不定式形式。

操作詞的語法特征如下：

1. 肯定句變否定句時否定詞not直接置于操作詞之后。

He will come tomorrow.

He will not come tomorrow.

He loved her.

He did not love her.

2. 非正式語體尤其口語中，操作詞可以和not構(gòu)成縮合式。（am的縮合式ain't只用于俚語）。縮合后為重讀。注意正式語體不可用操作詞和not的縮合式。

3. 參與一般疑問句和選擇疑問句的構(gòu)成：操作詞移至主語前，句末用問號，讀升調(diào)：

He is an English teacher.

Is he an English teacher (or math teacher)?

He wants to buy a car.

Does he want to buy a car (or a motorcycle)?

4. 反義問句（附尾問句）的問句部分構(gòu)成：操作詞 + 人稱代詞？（前否后肯，前肯后否）

You have two children, haven’t you？（英式）/don’t you?(美式)

He won’t come, will he?

5. 有的詞項前置時（如否定副詞或only加狀語），需要部分倒裝句，就是操作詞的倒裝：

   I have never seen this before.

   Never have I seen this before.

   He had scarcely finished his dinner when she came.

   Scarcely had he finished his dinner when she came.

   We had a meeting only when necessary.

   Only when necessary did we have a meeting.

   He gets up at six o’clock every day.

   When does he get up every day? (疑問詞前置導(dǎo)致部分倒裝。)

   Three students were late for class.

   How many students were late for class? (疑問詞本身就位于主語前，并無前置，所以不倒裝。)

（部分倒裝句（即操作詞的倒裝）是由前置導(dǎo)致的結(jié)果，前置的內(nèi)容是信息中心。

完全倒裝句（實意動詞的倒裝）是后移帶來的結(jié)果，信息中心在句末。）