当有人做出过于幼稚的举动时，会被别人说：“别没大没小的”，意思是让这个人举止成熟点，别闹笑话。那怎样用英语将这句话表达得简洁准确呢？

我们不妨举个例子：

Mr. Brown was playing tag with the children at the party. Then Mrs. Brown said, "Henry, act your age," and he stopped. 布朗先生在聚会上和孩子们玩捉迷藏，只听布朗太太说：“亨利，别没大没小的。”于是布朗先生不再玩了。

在上面这个例子中，act one's age就是指“举止与年龄相称”，有时也用be one's age来表示，用来形容孩子气。来看下面这个例子：

We children enjoyed our uncle because he didn't always act his age. 我们孩子们喜欢叔叔因为他时常很孩子气。

但act one's age的翻译常要结合语境。在下面这句话里，act one's age就不能说成“没大没小的”。

Bobby cried when he broke his kite. Mother said: "You are a big boy now. Act your age." 波比弄坏了他的风筝，哭起来。他妈妈说：“你已经是个大孩子了，就该像个大孩子样，别动不动就哭哭啼啼的。”