Our duty is to ______ their country against bothdomestic and foreign enemies’ attack

Have you ever been to HK, Jim—- Yes, I ______ there for two weeks with my parents last summer.

A dozen ideaswere considered _____ the chief architect decided on the design of thebuilding

You seemed to have been impressed by his songs.—Well, not exactly soIt was his way of singing____ his voice that really impressed me

The number of tickets _____ willbe determined by the size of the stadium.