20His parents were teachers in that school, _______ lost their lives in order to save their students in the earthquake

This is a complex operation. A team of nurses _____ the doctor in performing the operation.

In the spoken English of some areas in the US，the “r”sounds at the end of the words________

What kind of food is______ , Chinese food, Japanese food or the western food

I’d like to ___________whether Flight 245 for San Francisco is departing on time .