“焕然一新”，汉语成语，意思是改变陈旧的面貌，呈现出崭新的样子。通常形容出现了崭新的面貌。可以翻译为“take on an entirely new look，acquire a completely new look”。

例句：

经过翻修，我们的教学楼面貌焕然一新。

After renovation, our classroom building has taken on an entirely new look.