Weather ______, we'll go out for a walk.
Mary is the only one of the teachers who ________ a little Chinese because she is one of my friends who ________ been to China.
.________ surprising it is you should not know what has happened!
Not until I came home last night ________ to bed.
It was ________ he came back from Africa that year ________ he met the girl he would like to marry.
Barry must have visited the Eiffel Tower before,________he?