launch (v) The hot-air balloons were launched into the sky. Definition: to send or shoot

inflate (v) Billy asked me to inflate the balloon. Definition: to add air or gas to (something, such as a tire or a balloon) and make it larger Antonym: deflate

companion (n) My mom was my traveling companion when I toured Mexico. Definition: a person or animal to keep someone company

anchor (v) We anchored the boat and began to look for whales. Definition: to prevent a vessel from moving

scientific (adj) We used the scientific method to prove that air has weight. Definition: relating to science

particle (n) The scientists looked at particles under the microscope. Definition: a very small piece of something

dense (adj) The fog was so dense that school was delayed. Definition: having parts that are close together; heavy

hydrogen (n) Water is made of hydrogen and oxygen. Definition: a light gas that burns easily; it’s a chemical element that has no color or smell