Cách sử dụng
The word 'dud' means something that is broken, not working or not useful. It can be used to describe an object like a machine, a gadget or a tool that is not functioning properly. It can also be used to describe a person or an idea that is not successful or effective. For example, if a person buys a phone that is not working, they could say "this phone is a dud". Or if someone comes up with a plan that is not going to work, someone else could say "that's a dud idea".