Cách sử dụng
The word 'knock' is used when you hit or tap on a door or surface to make a noise. For example, when you arrive at someone's house, you might knock on their door to let them know you're there. You can also use 'knock' when talking about hitting a surface with your knuckles, like knocking on a table to get someone's attention. It's important to be polite and not knock too loudly or aggressively.