talk big 说大话;吹牛;吹牛，说大话;说大话,吹牛;放空炮

【例句】
He likes to talk big as if he was an important person.
他老爱说大话，就仿佛他是一位要人似的。

We dislike those who talk big and do nothing.
我们不喜欢那种夸夸其谈，不干实事的人。