How long does it take to get to the airport?—Forty minutes. But it’s foggy today. I’m not sure the highway will closes soon. Let’s set off earlier.

I took the wrong train .I didn’t even know it until half an hour later. [ ]

My father is busy _____ the moment. [ ]

Mr. Black, I find ______ difficult to play the piano well.—Oh, I think you just need to practice more

What is Nancy going to be when she________?__Maybe she is going to be a math teacher.