.Susan’s parents have bought a large house with a swimming pool. It ______be very expensive.

 Sorry I’m late. I ____ have turned off the alarm clock and gone back to sleep again. 

--- May I go now? --- No. You ______________ let the teacher know first.”

I like playing        basketball and playing        erhu. 

Is that your best friend Kitty?— No, it _________ be her. She flew to Singapore yesterday.