--I don't think we have met before.--Yes, once at a party, but we___________.
---Where did you meet him? ---It was in the hotel ______ he stayed ______ I met him.
The foreign visitors couldn’t help ________ by the beautiful scenery of the Great Wall.
_____ two English exams to worry about, I have to work really hard this month.
_______ to the discovery of radium, Madame Curie plays an important role in modern science.
The couple _________ last week, which surprised their friends and relatives greatly because they appeared that happy all the time.