1 arrived
2 were pouring
3 noticed
4 was reading
5 was climbing-collapsed
1 b did,went,had to-Past Simple
2 d. were working-Past Continuous
3 f. did,had,worked-Past Simple
4 g. did,forgot -Past Simple,was working-Past Continuous
5 e. was doing,was visiting -Past Continuous
6 a. happened,snapped-Past Simple,was lifting-Past Continuous
7 c. did-Past Simple