Subject-auxiliary inversion is triggered by fronting certain negative or restrictive adverbials (Never, Rarely, Not only, No sooner, Hardly, Under no circumstances), and also by so/such fronting for degree (So loud was the noise…) and comparative structures (As did his predecessor…). These structures are hallmarks of formal writing and rhetoric.
After certain negative/restrictive adverbials, the auxiliary comes before the subject. Choose the correctly inverted sentence.
Subject-auxiliary inversion places the auxiliary before the subject. It is required after negative/restrictive adverbials, and after fronted so/such for degree.
| Trigger | Structure | Example |
|---|---|---|
| Never / Rarely / Seldom / Scarcely / Barely | Never + have/had/did + S + V | Never have I felt so proud. |
| Not only… (but also) | Not only + aux + S + V | Not only did she win, but she also broke the record. |
| No sooner… than | No sooner + had + S + pp + than | No sooner had I sat down than the phone rang. |
| Hardly / Scarcely… when | Hardly + had + S + pp + when | Hardly had we arrived when it started raining. |
| Under no circumstances / At no point / In no way | + aux + S + V | Under no circumstances are students allowed to cheat. |
| Only after / Only when / Only then / Only by | Only… + did/can/could + S + V | Only after the meeting did we learn the truth. |
| Not until | Not until + clause/time + did + S + V | Not until she left did he realise how much he cared. |
| Little | Little + did + S + know/think/realise | Little did they know what lay ahead. |
| So + adj / adv (degree) | So + adj/adv + was/did + S | So loud was the music that neighbours complained. |
| Such + NP (degree) | Such + was + the + noun | Such was her determination that nothing could stop her. |