Cách sử dụng
The expression "bob up" means to suddenly appear or come into view. For example, if you are waiting for your friend to arrive and suddenly they appear around the corner, you can say "there they are, they just bobbed up!". It can also be used when something appears unexpectedly, like a question that suddenly comes to your mind or an idea that pops up in a conversation. "Bob up" can be used in both formal and informal settings.