下决定用英文怎么说

下决定的英文：
solve

Will you help me to solve this twister?
你能帮助我解决这个难题吗？

I just solved the mystery.
我刚刚把那个谜底解开了。

It was a physical problem that had to be solved.
要解决的问题是个实际问题。

The case should be solved liberally.
这件案子应该被公平处理。

We have no trouble in solving this problem.
解决这个问题，我们没有困难。