qustions regarding Cliche and idiom

[LeTyan]

For people(like me) who study English as a second language, Cliches and idioms can sometimes be questionable when it comes to learning. Idioms are obviously useful, but what are Cliches? Should people like me still need to understand those or should I simply ignore them?
For example, "Let bygones be bygones." "Add insult to injury." They are marked as Cliches in an online dictionary. So do native speakers acutually still use them? Do those still have the values for language learning?

Thanks!!!

[Raymott]

For people(like me) who study English as a second language, Cliches and idioms can sometimes be questionable when it comes to learning. Idioms are obviously useful, but what are Cliches? Should people like me still need to understand those or should I simply ignore them?
For example, "Let bygones be bygones." "Add insult to injury." They are marked as Cliches in an online dictionary. So do native speakers acutually still use them? Do those still have the values for language learning?

Thanks!!!

Yes, you should learn them. You need to understand them, but you don't have to use them.

[Tdol]

Clichés are phrases that are overused and have lost some of their impact. I would be happy never to hear at the end of the day as a way of introducing a conclusion, but it is so common that it is a good idea to know it.

[Jessica63]

You don't have to memorise cliches, but there are so many in use, it's good to know a few of them.

[BobK]

(Avoid them like the plague. )

b