After studying all day, I like to relax.
A time clause can be shortened to a time expression plus an -ing form. The meaning is identical — the sentence is just tighter and more formal.
Before I played it, I never thought I'd enjoy it.
Before playing it, I never thought I'd enjoy it.
× the subject
× the tense
The route depends on the time expression you start with.
Keep the time expression, delete the subject, change the verb to the gerund.
Delete as soon as, replace it with on, remove the subject, use the gerund.
A reduced clause has no subject of its own, so it borrows the subject of the main clause. If the two subjects differ, you cannot reduce.
I locked the door before I left.
→ I locked the door before leaving.
Before I left, the phone rang.
→ Before leaving, the phone rang. (the phone didn't leave)
After I studying all day, I like to relax.
Correct: After studying all day…
…I never thought I'd enjoy it before to play it.
Correct: before playing it.
As soon as arriving home, we started dinner.
Correct: On arriving home…
On hear the news, he burst into tears.
Correct: On hearing the news…
Say the answer out loud — then tap to check.
WhileA waitedB for the bus, she readC two chapters ofD her book.
Bwaited → waiting
✓ a reduced time clause takes the -ing form
AfterA checkingB the figures, the accountant signedC the report, although the totals was wrongD.
Dalthough the totals was wrong → although the totals were wrong
✓ the totals is plural → were
Before leaveA the office, youB mustC switch offD the lights at the main panel.
ABefore leave → Before leaving
✓ before + -ing in a reduced time clause
Use before / since / after + -ing or on + -ing.
Two subjects, no reduction — check them before you cut.