both
propeller
Blood cells are a part of blood. Blood is not a part of blood cells. Blood can't flow backward and forward within blood cells. Blood cells can flow backward and forward within blood.
An ollie is a skateboard trick. And an ollie is a vital part in almost every trick.
Eye.
of course you can!
Its the forward part of the boat
Its the wooden bit which you stand on. The main part of the board.
It is called the trucks
Street Luge
It is called the trucks
"Backwards" is an adverb: "The car moved slowly backwards along the street."
The idea of counterbalancing is like see-saws or scales. You use the weight a part of your body in different positions to equal the the lighter or heavier part of your body to. Example: When you do a arabesque or a scale you lean forward as your leg goes up backwards to counterbalance your weight.