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.
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.