A.a bug
B.a bee
C.a bull
D.an ant

A.tuition
B.debt
C.livelihood
D.finance

A.protected
B.held
C.assured
D.defended

A.take up
B.turn round
C.put off
D.do with

A.produce
B.productive
C.production
D.productively

A.Having invited
B.To have invited
C.Having been invited
D.To have been invited

A.Before she came to London
B.By the time she comes to London
C.While she was in London
D.After she came to London

A.Although
B.Despite
C.Because
D.Because of

A.seriously
B.insignificantly
C.largely
D.commonly

A.Every student might write an essay on the topic.
B.Every student must write an essay on the topic.
C.They require every student can write an essay on the topic.
D.Every student should write an essay on the topic.