Inversion
Inversion occurs when we change the order of the subject and the verb in a declarative sentence after an adverbial in initial position. It is used for emphasis, in more formal or poetic discourse, and in some day-to-day fixed expressions. Inversion only occurs if the sentence contains an auxiliary verb, modal verb, or the verb be.
The following are some common adverbials that can be used with inversion.
at no time, little, never, not until, nowhere, only after, only then, only later, rarely, seldom, scarcely, under no circumstances