A.exercise
B.policy
C.skill
D.habit

A.initial
B.ancient
C.unique
D.perfect

A.initial
B.ancient
C.unique
D.perfect

A.delay
B.inaction
C.standstill
D.gridlock

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