Answer:
I know a word of letters three. Add two and fewer there will be. What is the word?
I keep things green and keep kids happy during summer time.
The dirtier I get, the whiter I am. What am I?
In all the world, none can compare, I am a tiny weaver; my deadly cloth so silky and fair. What am I?
lighter than feather and softer than silk yet the strongest man in the world cannot hold me for more than a few minutes.
Give it food and it will live, give it water and it will die.