这真是色彩的一种妙用！

Now that's a useful use of color!

大约在这个时候，我发现了钥匙的妙用。

About this time I found out the use of a key.

有了零钱不用愁，妙用乐为新举措！

A new campaign capitalizes on some fiendish and funny USES for loose change.

王世厚的气消了，便给儿子讲人粪、牛粪、猪粪、草木灰的妙用。

Wang Shihou aren't angry and he teaches the refinement of human dung, cow dung, manure and plant ash.