—How long have you known the doctor ? — he helped me three years ago.
I think the place has changed ______ over the last years.
A: _____ do you know the book on the left?B: I know it very well.
Look! The reporter from CCTV is having an interview ______ Mr Zhou.
A: Could I clean the bedroom for you ?B: No, thanks. I ______ it myself.
Is there ____ European wolf in _____ zoo?