Answer:
I help engines spin and pants stay up
Some will use me, others not. Some have remembered, others forgot. For profit or gain, I'm used expertly. I can't be picked off the ground or tossed into the sea. What am I?
I have a little pool with two layers of wall around it. One white and soft and the other dark and hard. Amidst a light brown grassy lawn with an outline of a green grass.
I build up castles. I tear down mountains. I make some men blind, but I help others to see. What am I?
Tuesday, Sam and Peter went to a restaurant. After eating lunch, they paid the bill. Sam and Peter did not pay. Who did?
Give it food and it will live, give it water and it will die.