Inversion of the verb after certain adverbs

In this article, we're going to have a look at inversion that sometimes takes place with certain adverbs and adverb phrases, mostly with a negative or restrictive sense. Such adverbs (adverb phrases) can be placed first in a sentence or clause for emphasis. They are then followed by the interrogative (i.e. inverted ) form of the verb.

The most important of these adverbs include:

• hardly ever
• never
• scarcely ever
• only by
• in no circumstances
• only in this way on no account
• hardly . . . when
• only then/when no sooner . . . than
• scarcely . . . when
• not only
• seldom
• nowhere
• not till
• so
• neither/nor

Examples of how to use them:

• I had never before been to lie. =
  Never before had I been asked to lie.
  
• a) / haven't got any money.
  b) Neither/Nor have I.

• They not only rob you, they smash everything too. =
  Not only do they rob you, they smash everything too.

• She became so depressed that. . . =
  So sepressed did she become that. . .

• This switch must not be touched on any account. =
  On no account must this switch be touched.

• Mike didn't realize how difficult how situation was till he received the letter. =
  Not till he received the letter did he realize how difficult his situation was.

Also note that a second negative verb in a sentence can sometimes be expressed by nor with inversion:

She had no friends and didn't know anyone who could help her. =
She had no friends, nor did she know anyone who could help her.

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