1. He looks like he’s about four years old.

(He’s almost four.)

2. She’s about 12 years old.

 3. When he woke up, there were about ten people waiting for his garage sale to begin.

 (garage sale: a homeowner sells unneeded, personal items from his or her garage)

 4. He’s been on the phone for about ten minutes.

 9. She’s reading a very interesting book about European history.  

(In this example, the word “about” refers to the content of the book.)