Cách sử dụng
The expression "be on the phone" means that someone is speaking to someone else through a telephone. It is used when we want to talk about someone who is using their phone to make or receive a call. For example, if you call your friend but they do not answer, you might say "I think they are on the phone." Or if you see someone talking on their phone, you might say "They are on the phone right now." It is a common expression used in everyday conversation.