Do you know the reason ________ pilots turn off the plane’s lights before taking off?— The practice is for the passengers to adjust to the dark ________ an emergency[ ]

Everybody is here ________ Tom ， because he is ill in hospital .

Has Linda finished her homework—Sorry, I don’t know. I just saw that she _____ it yesterday afternoon.

The chance will be given to only ________ students, so ________ of you should try hard to catch it.

Bob swims _______ than I, but he doesn’t swim my brother.