– 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·

How _____ you say that you have made great progress since there are so many mistakes in your test paper ? 

We apologize for any inconvenience you _______ have been caused by the delay of the flight.

They demanded that the library _____ open to students during the vacation.

How I wish I ____ the mistake! Everybody present was angry with me.