___has recently been done to provide more buses for the people ,a shortage of public vehicles remains a serious problem .
_________ smoking, he would not have got cancer in the lung.
---“What do you think of the service here?”---“Oh, _________ . We couldn’t have found a better place.”
Modern forms of transportation and communication have done much to ______ the isolation(隔离)of life in Alaska.
If you don’t try your best to learn all subjects, you will ___ behind.
Entering the room,I found Mary____ at the desk and____ a letter.