Where, when, why, and what time

(a) Where did you go? Paris
(b) Why did you stay home? Because I didn’t feel well
(c) What time did he come? Seven-thirty, around five o’clock, a quarter past ten
(d) What did he come? Seven- thirty, Last night, Two days ago, Monday morning, In 1998
Where ask about place
Why ask about reason
A question with what time asks about time in a clock.
A question with when can be answered by any time expression, as in the sample answer in (d)