Is that your best friend Kitty?— No, it _________ be her. She flew to Singapore yesterday.
My work is interesting, but _____ dangerous.
____________ our football team failed in the match, we did our best.
____________ they are brothers, they look like each other.
We will spend our summer holiday in Guilin, but we haven’t decided______________.
— When _________ you________ your teeth, Billy? —Just now.