vast

公司在研究上投入了巨额资金。

The company invested a ___vast sum of money in research.

我们在旅行中驾车穿过了广阔的森林区域。

We drove through ___vast areas of forest during our trip.

这个国家拥有巨大的自然资源储备。

This country has a ___vast reserve of natural resources.