The man didn’t know _________ the thief broke into the house and stole all his valuable things

The water _____ cool when I jumped into the pool for morning _____

Where’s your brother —He ________ the library with his friend. He’ll be back soon.

Our city has developed into a big city；which is ____ it used to be.[ ]

Have you ever been to HK, Jim—- Yes, I ______ there for two weeks with my parents last summer.