— How do you deal with the disagreement between the company and the customers?— The key _____ the problem is to meet the demand _____ by the customers.
The reason _____ he gave for not coming to your birthday party is ______ his mother was ill.
Who do you think the teacher will ______ the question?
The man will have to wait all day ______ the doctor works faster.
With a lot of difficult problems ______, the newly-elected president is having a hard time.
I used to quarrel a lot with my parents, but now we _______ fine.