Write the correct alternatives

a) I HAD LIVED / LIVED in London for a long time before I LEARNT/HAD LEARNT to speak English fluently.
b) Before we CAME/ HAD COME to this country, we HAD NEVER TRAVELLED/DIDN’T TRAVEL by plane. c) I HAD FINISHED/ FINISHED all my homework before I HAD MET/ MET my friends.
d)When my friend CALLED/HAD CALLED, I HAD JUST HAD/ JUST HAD my breakfast.
e)We HAD STUDIED/ STUDIED hard before we TOOK/ HAD TAKEN the test.