1) When we arrived at the island,
it had been raining for seven days.
2) By the time they finish the bridge next year, they
will have been working (OR will have worked?) for twenty years.
3) I wish
I didn't have to write this letter.
4) Jenny advised (
a) that we should buy the tickets in advance, b) to buy our tickets in advance, c) everyone to buy their tickets in advance ).
5) The actor managed to perform
( a) despite his sore throat, b) even though he had a sore throat (sounds better [Y]
)
).
6) We expected the project
to have been completed by now ( would have been completed by now???).
I'm taking my final English exam in June and I want to prepare properly

Thanks in advance.