⦁ When you exercise, your muscles become / blood becomes bigger and stronger.
⦁ The heart / bone is a big muscle and it beats about 100,000 times a day.
⦁ The brain / Blood is red and it goes to all parts of the body.
⦁ The hearts / bones in your legs and arms are the longest in your body.
⦁ Do intelligent animals have a big brain / blood?
