Lost in the mountains for three days, what the three men were able to do was the help of helicopters.
The engine of the ship was out of order and the bad weather _____ the helplessness of the crew at sea.
The electric library made it impossible for teachers to have ______ to a large amount of information online.
Some kinds of birds in winter fly to the south to ______ the cold in the north.
We must apply what we have learned to our daily work because in no case _____ from practice.
The earthquake of 2008 was extremely terrible. ___ it was the worst disaster we had ever seen.