20.This is the small house less than 15 square meters,under _____ roof lives a large family of three generations.
If my car _________more reliable, I would have driven to Lhasa instead of flying last summer.
-I'm sorry for being late. I should have phoned you earlier. --. I've just arrived.
________ in a long queue, we waited for the store to open to buy a New iPad .
It is the third time that she has won the race, ______ has surprised us all.
No matter where he is, he makesa rule to go for a walk before breakfast.