Only when I made it to the train station _______ that I had left my ticket at home.

The boss didn’t _____ to the workers’ request for increasing their wages(工资).

Happy birthday, Alice? So you have _______ twenty-one already?

How long can I keep the book? —-A week．You _____to return it by Monday

I think watching TV every evening is a waste oftime—there are ____ meaningful things to do.