Question 1. Are these sentences correct?

  1. He saw me after he had entered the room.
  2. He saw me after entering the room.
  3. Entering the room, he saw me.
  4. On entering the room, he saw me.
  5. Upon entering the room, he saw me.
  6. Having entered the room, he saw me.

Question 2. Can we start a sentence with any verb preceded by on or upon?

  1. On coming home, he fainted.
  2. On starting the job, he sent me a message.
  3. On solving the problem, he left.
  4. On cooking dinner, she asked for help.

1 Answer 1


Regarding the first question, all of those are grammatical for sure. 3 and 4 are a little awkward, but you could use them and be understood. Also, I'm fairly sure 6 has a slightly different meaning than the rest of the sentence; the emphasis is more on the fact that he entered the room, not so much that it happened right when he walked in the room. It's more analogous to "Because he had entered the room [at some point in time], he saw me."

[Edit: Regarding the second question,] If you want to sound more natural, you're probably better off using "when", but yes, those are all correct.

  • 2.4 seems to me to be different from the others. 'On [doing something]' usually means at the moment of doing it, or soon after, but 'cooking dinner' is an action that takes some time. Do you mean 'She asked for help with cooking dinner', or 'Having cooked the dinner, she asked for help [with something else]'? Commented Apr 28, 2020 at 9:02
  • The sentence implies one action taking place after another. I just wanted to make it clear for myself as to whether it is possible to use the preposition 'on' before any verb to mean somebody did something after a certain action. Having cooked dinner, she asked for help. On cooking dinner, she asked for help. Having arrived home, he called me. On arriving home, he called me. Commented Apr 28, 2020 at 23:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .