Cách sử dụng
The expression "practise what you preach" means that you should practice what you tell others to do. It is often used to remind someone that they should not give advice or instructions that they do not follow themselves. For example, if you tell your friend to quit smoking but you continue to smoke yourself, someone may say to you "practice what you preach" to remind you that you should quit smoking too if you want your advice to be taken seriously.