— Miss Lin _____ my desk-mate with her lessons when I left school.—She is really a nice teacher.A. helps B. is helping C. was helping
The Jiangs have lived in the city of Nantong since__________.
I found _______ difficult to work out the problem.
The Greens used to live in London and now they ________ in Beijing.
The train was travelling _______ low speed at that time.
— Have you ever been to Sanya? — Yes, ________already.