– Mum, would you please buy me a MP5 player?– If you can help do the dishes the whole vacation，you________have one as a reward·

I can’t believe that anyone else in the school can swim as fast as you, ________?

-You must call them every week.　-Yes, I _____.

According to the air traffic rules, you ___ switch off your mobile phone before boarding.

—Could I have a word with you，mum?—Oh，dear，if you _____．