Doctors recommend that all children ________ vaccinated against measles(麻疹).
----The cake smells delicious. ---- ____.
----It's too late now. I think it's time for me to leave. ---- ____.
Is this school ____ you studied at ten years ago?
What the boy ____ make his friends happy.
He was so pleased with all ______ we had done for him _____ he wrote us a letter to praise us for it.