Choose the right tense.
a) When I was arriving/arrived at Dan’s house, he was waiting/waited outside.

b) While we were doing/did a maths test, the head teacher was coming/came into the room.

c) While we swam/were swimming, it started/was starting to rain.

d) While I was having/had a bath, the lights were going out/went out.

e) Debra watched/was watching television when the storm began/beginning.

f) While I was walking/walked to the shop I was losing/lost my bag!

g) What were you doing when I was seeing you yesterday?

h) I was walking/climbed up the stairs when I was hearing/heard the phone.