Advanced time clauses use inverted structures with no sooner...than, hardly/scarcely...when, and not until to create formal, emphatic sentences. These structures are common in academic writing, journalism, and literary prose.
No sooner...than (with inversion)
Place No sooner at the start, invert had and the subject, and follow with than for the second event.
No sooner had I arrived than the phone rang.
No sooner had the announcement been made than protests erupted.
Hardly/Scarcely...when/before
Start with Hardly or Scarcely, invert the auxiliary and subject, then use when or before for the interrupting event.
Hardly had she finished speaking when the audience applauded.
Scarcely had they arrived before the storm hit.
Not until...did (with inversion)
Place Not until at the start, then invert the main clause with did + subject + base verb.
Not until the results were published did the researchers realize their error.
Not until midnight did the negotiations reach a conclusion.
Common mistakes
Not "No sooner I had arrived than the meeting started." — say "No sooner had I arrived than the meeting started.". After 'No sooner,' the auxiliary 'had' must come before the subject (inversion is required).
Practise it
Remember the pairs: No sooner...than, Hardly...when, Scarcely...before. The first clause always uses past perfect with inversion.