It’s foggy today. I’m not sure             the highway will close soon. Let’s set off earlier.

—How about joining us in the summer camp? —I wish I could, ___________ I have to practice for the piano test. 

–Little boy, don’t play with the knife, __________ you’ll cut your hand.  –Sorry, I won’t.

Good to see you again. It’s almost three years _______ we met last time.

The boy didn’t go to school ____________his illness(疾病)。