I want to be ______engineer, but my best friend wants to be a policeman.
---What do you think of the book?---Wonderful. In fact, I’ve never read a _______one before.
---Look! It must be Jack on the playground.---It _____ be him. Because I saw him enter the school library just now.
---Have you found the information about the famous people ______ you can use for the report?---Not yet. I’ll search some on the Internet.
---Did you go to Tom’s twelfth birthday party last Sunday?--- No, I ________ .
In some foreign countries, such as Canada, children usually leave their parents when they grow up. It makes the old feel_______.