He _____ a visit to the factory and was warmly_____ by the workers there

Perhaps most puzzling of all, _____ able to make sense of _____ we heard and distinguish the mistakes and errors from “good” language?

The terrible accident is under investigation. — Actually, quicker action _________ those workers trapped in the mine.

_______ is known to us all that the 2010World Expo took place in Shanghai.

As high school students, it’s very important to keep ourselves ______ of what’s happening home and abroad every day