Reading Comprehension No. 1 How Things Move... We can watch things around us move.! When something is in motion, it changes its position.! objects can move from one place to another.! They can move in many directions.! If you roll a ball, it might move in a straight line.! It might also move in a curve. A swing can move back and forth.! A light switch can move up and down.! Fans have blades that move in a circle.! If you want to know if something is moving, you can compare it to other things around it that are not moving.! If the things behind the object are changing, the object is probably moving.! If they are not changing, the object is probably not moving.! You can measure the distance an object moves.! Just measure the distance between where it was when it started to move and where it was when it stopped.! Distance can be measured in inches, feet, yards or miles.! Those measurements are in the customary system.! It can also be measured in millimeters, centimeters, meters and kilometers.! Those measurements are in the metric system.!