Our math teacher ________in our school for 20 years and he ________here when he was 23 years old.
I can’t play the piano,and________.
She’s not strong enough________walking up mountains.
—Could I borrow your camera? —________,but please give it back by Saturday.
—Sir,could you please put out your cigarette?This is a smoke-free(无烟的)school. —________.
Few people think about what they can do________others.