明珠暗投的英文：
[Literal Meaning]
bright/pearl/cast/darkness
to cast pearls into darkness

[解释]
比喻有才能的人得不到重视。也比喻好东西落入不识货人的手里。

[Explanation]
The talented are neglected or something valuable is not recognized.

[例子]
把这么好一件玉器送给她真是明珠暗投，她根本不懂什么是艺术。

[Example]
Giving her this piece of jade artwork was totally to cast pearls into darkness. She did not know what art really meant.

[英文等价词]
to cast pearls before swine

Never cast your pearls before swine.
不要把珍贵之物送给不识货的人;勿明珠暗投;勿对牛弹琴。