选词填空

used to, pass away, fall behind, add up to,   end up, make sense,   face to face,   give away,   apply oneself to,   drop out

【小题1】Jane was very sad after his dog ___________ after 10 years.
【小题2】For a hit show, profits can __________ millions of dollars.
【小题3】Her father __________ go fishing in the lake.
【小题4】He often __________ his research, forgetting to have meals.
【小题5】David __________ of high school at the age of 15 to help his father on the farm.
【小题6】Unless you study hard, you will __________ failing the exam.
【小题7】Please believe in me. I will never __________ your secrets again.
【小题8】We had better talk about this __________.
【小题9】One will _______ the times if one does not acquire new knowledge.
【小题10】It _____ to take regular exercise to keep fit.