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

___ a lot of work to do, all the workers are not allowed to take their holidays.

Have you heard of it ? Firefighters rushed into a burning house, three of them unfortunately       in and         their lives.

_______ only one week left before the final examination, we’re kept busy going over our lessons.

When I passed this afternoon ,I saw Mary lying on the grass, her hands        under her head.