Was it in 1969 _____ the American astronaut succeeded ____ landing on the moon?
. How can you expect to get everything ______ you never give?
Meeting my uncle after all these years was an unforgettable moment, ______ I will always treasure.
. The country has already sent up three unmanned spacecraft, the most recent ______ at the end of last March.
. What the doctors really doubt is ______ my mother will recover from the serious disease soon.
In order to improve English _____.