Foodsafetyissues,____willseriouslyaffectthegrowthofteenagersandeventhenation’sfuture. [ ]

What ________ useful book ! —Yes, it is. But I found___________difficult for me to read.

The little boy is but he can speak Chinese.

Liu Ming is said abroadfor one year before he came to teach in our school．

eatest pleasure I know is to do a goodaction quietly, and to have it _____ by accident.