I work hard at school. I think I _______ a teacher someday.

Many strange new means of transport have been developed in our century, the strangest of _____ being perhaps the hovercraft(气垫船).

The island is quite hot all year round，because it’s _________ the equator.

The constitution, unlike other forms of laws, is fundamental ______ our social system working properly[ ]

Your luggage is overweight, so you must decide what to______.