It was not until the beginning of the twentieth century________to explore space.
—____________ difficulty you meet, remember that it might just be a touchstone. —You are right. __________ difficult it is, we will never give in.
We haven’t seen ________ of her films, but ________ from the one I have seen recently, I think she is a promising actress.
He fell in love with the beautiful scenery at the first sight, and _________ it ever since.
It is reported that two schools, ________ are being built in my hometown, will open next year.
Was it in the factory _____ you worked five years ago ____ you met your wife for the first time?