—______ do they get a present for their mother?—Because it’s their mother’s birthday.
You will be late for school ________ you don’t get up early.
Animals are our good friends. We are supposed ________ them.
–Have you ever been to Guilin?--No, ________. I hope I can go there next year.
During summer, lots of people swim in the pool, so it is very ________.
There were more than four ________ passengers on the ship named Eastern Star(东方之星) when it sank.