We can never forget the days _______the two astronauts in spaceship worked together and the days _______we spent together.
___ by the beauty of nature, the girl from London decided to spend another two days on the farm.
The house _________ now used to be a storeroom.
The boy kepthis mother for more chocolate,and finally his mother.
____ a computer works is a question ___ not everyone cad answer quickly.
All passengers ______ are expected to fasten the seat belts when the plane takes off and lands.