Those who _________ singing may join us.

Each of the students in our class　　　　great interest in English and we each　　　　a copy of A New English­Chinese Dictionary. 

The country’s population     small, and most of its population      in the mountainous areas.

 Many a student _____ playing games on the playground and only one girl or two _____ reading in the classroom. 

 Every possible means_____ been tried，and we find only______ this means can we do it well．