The elder brother’s names are wood and metal respectively, and the younger brother can choose water, fire, or earth.
Water: Zheng Lixi (Stream: taking the meaning of the best water, benevolence and wisdom found in the ordinary), Zheng Lize (Ze: favor; luster), Zheng Liming (Ming: sea, there are fish in the north, showing the child's mind and future (Liaoyuan)
Fire: Zheng Liyan (I am reminded of the great Confucian Zhang Taiyan)
Earth: Zheng Lipei, Zheng Lizhen
And so on, you can look for water, Regarding the characters of fire and earth, I just recommended a few that I think are pretty good. I hope it can give you some inspiration:) Funny~~