When I (to enter) the hall, the students (to listen) to a very informative lecture on...

Question

When I (to enter) the hall, the students (to listen) to a very informative lecture on history of the English language.

Answer 1

Entered, were listening

Answer 2

When I entered the hall, the students were listening to a very informative lecture on history of the English language.  

1- past simple 2 - past continious

Comments

когда сможешь выбери лучшим