What’s your favorite subject— English. I like it very much ________ it’s interesting and useful.

Could I please use your bike—.I have to go out.

She bought a digital camera online__________ she saved a lot of time

It was not until I had read your e-mail _____ I understood what you had done for the students.

Many teenagers don’t get enough sleep because they have too much homework, which _____ them up at night.[ ]