At no time did the company break the law.
Compare: The company did not break the law at any time.
Under no circumstances should you travel alone.
Compare: You should not travel alone under any circumstances.
Never in my life have I seen such extraordinary behaviour.
Compare: I have never seen such extraordinary behaviour in my life.
The telephone had been disconnected. Nor was there any electricity.
Compare: There wasn't any electricity either.
Seldom did we have any time to ourselves.
Compare: We seldom had any time to ourselves.
Only in summer is it hot enough to sit outside.
Compare: It's only hot enough to sit outside in summer.