Achieving a high degree of proficiency(精通)in English as a foreign language is not a mysterious _______ without scientific basis.
—Which of these two books will you take?—I’ll take ______, in case the journey is boring.
I know this is not quite the right word, but I can’t be bothered to think of _____.
I am looking forward to ______ your answer as soon as possible.
The teacher as well as the students who ______ fond of football, ______ playing together.A. are; is B. are; are C is; are D. is; is
Everything went on as usual ______ nothing had happened.