Natural english

One day when he was watching TV, he saw an advertisement. 
A public speaking contest was going to be held in London.
Did he see a leaflet when he was watching TV?
Yes, he saw an advert when he was watching TV.
Was there a competition going to be held in London?
Yes, there was a contest going to be held in London.
Was there a contest going to happen in London?
No, there wasn’t going to happen a contest in London.
Was he eating vegetables when he saw an advertisement?
No, he wasn’t eating vegetables when he saw an advert.
Was he cutting the tree down when he saw a leaflet?
No, he wasn’t cutting the tree down when he saw a leaflet.