If we had taken such effective measures much earlier, the river so seriously now.
To learn English well, you should ______ as many words and expressions as possible.
David studied hard before the examination, and it ______. He made an A. A. worked out B. marked out C. paid off D. got through
______ label to each of the trees, with detailed introduction of their features, and visitors will know more about them and how to protect them.
---Who is to give us the lecture today? ---The lady _____ our headmaster into the hall.
Those who don’t get their sufficient sleep are actually sending a(n) _____ to severe problems in their life.