Cách sử dụng
The expression "cotton on" means to understand or realize something after not being aware of it before. For example, if you didn't understand a joke at first, but then suddenly understood it, you could say "I finally cottoned on to the joke!" It can also be used to describe someone who finally realizes that they are being tricked or deceived. This expression is often used in casual conversation and is more commonly heard in British English than American English.