He tried his best to solve the problem, _______ difficult it was.
30. With _______ production up 60%, the car company had another excellent year.
29. Instead of leading us a hand, he just stood by, __________________us when we were in trouble.
28. Have you adapted _______ in a different country?
27. To learn Engli8sh well. We should find opportunities to hear English _____ as much as we can.
26. I am not surprised that he became a writer. Even as a child he had a ______ imagination.