In that school, English is compulsory for all students, but French and Russia are ____ .
The reason _______ his going to Britain was ______ he got a new job there.
_____ with the size of the whole earth, the biggest ocean does not seem big at all.
People often use plastics to ______ wood or metal.
He convinced me ______ the difficulty of the work.
.If you are unable to attend the interview, for __________reason, you should inform us immediately.