___________there are many different types of food, some animals spend their lives eating only one type.

       published fifty years ago, his work still attracts much attention at present. 

____ she goes, there are crowds of people waiting to see her.

We were going out for a walk ________ it began to rain.

. --- What else do you want to know about the cell phone? --- _______ it can be used as a digital camera. You know, I’m into photography.