It is said that the temperature is unusual mainly ________ global warming caused by human activities.
The experiment shows that proper amounts of exercise, if regularly, can improve our health.
This coastal area a national wildlife reserve last year.
The boy disappeared in the village five years ago and he ever since.
We've had a good start, but next, more work needs ________ to achieve the final success.
——Have you heard about that fire in the market? ——Yes, fortunately no one .