Shall we finish the project two days ahead?—I’m afraid we , in case the heavy storm comes suddenly.

What color is it —— It’s _________.

下列各组句子中加横线字的意义和用法完全相同的一组是（ ）

Jogging is an effective way to keep fit ___, swimming is helpful for bodybuilding[ ]

. As a result of destroying the forests, a large ___ _ of desert___ covered the land.