—Oh, I had a terrible toothache! —You’d better go to see a doctor and have your tooth out.
—Look! The lights in the classroom are still on. —Oh, I forgot ________.
She found ___ hard to finish the work by herself.
Good learners aren’t afraid _______mistakes. Instead, they learn ________mistakes.
My parents want to go ____ on vacation.
Why not consider _________ Kunming next holiday?