When asked to explain_______ he did to make his students so fasinated with his lessons, the teacher paused and thought deeply.
Someone called me up in the middle of the night, but he hung up ____ I could answer the phone.
------ What made little Tony so unhappy and cry in his room? ------- _________to go biking with his brother.
----- Sally is strongly against taking the trip to Hainan. ----- _______? It was she who suggested the plan.
Was it not until you began to work ____ how much time you had wasted?
_____ some teenagers don’t realize is ____ difficult life can be after they get addicted to drugs.