21.The moment we heard the news of the earthquake, we began to ________ the work to rescue those who were trapped in the building.
Thank you for sending us ____ fresh vegetables of many kinds. You have done us ____ great service.
Which sentence is wrong?
I found the homework was not so heavy as ________ I ________ to get in my old school.
The hotel _____ during our holidays stands by the seaside.
He has lost the key to the drawer _____ the papers are kept.