My sister has_____ been to the Summer Palace. I ’m going to take her there.A.everB.som

.The old paper mill has been ______to make way for

Telecommuting—substituting the computer for the trip to the job—has been ______ a solution

My watch has been losing time for the past week. It probably needs_____.A. cleaningB.

My parents have_____ been to the Great Wall.A. sometimeB. neverC. yet

His sister left home in 1998, and _______since.A. has not been heard of B. has not bee

The conference has been held to discuss the effect of tourism ________the wildlife in