翻译；（1）掌握一门外语是很有帮助的 （2）跟他讲每用，因为他根本不听

It's helpful that we (should) study a foreign language.
It's useless to talk to him, because he doesn't listen to us at all.
注意，第一句是虚拟语气。
哈哈你好像是在写作业，有很多问题么，可以在线问我。