—Whose model plane is it?—It’s Jack’s. He made it by _______.
Nobody helped me. I finished it by _________.
My pen pal Ann found it difficult ______ Chinese well.
---Can you tell me why you learn English so well ? ---It is very simple. _______ you work, ______ grades you will get.
---How is Susan? ---Oh, she lives abroad, so I ______ ever see her.
---Why are you in such a hurry, John? --- There _____ a basketball match between Class2 and our class in 10 minutes.