To unite things or people is to bring them all together into one group. When people unite, they join together and become a single team, club, family, or group.
You and your friends could unite to reach a goal together, like cleaning up a local park.
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The United States is a nation of many states that have united, or joined together, under one government.
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If people reunite, they get back together as a group--after they'd been split up or separated. If you haven't seen your friends all summer, you'll be so happy to reunite with them on the first day of school. This girl and her mom are reuniting after being apart.
Remember: when you unite two or more things, you combine them so that they stay in a group or work together as one. The prefix "re-" can mean "again," so when people reunite, they get back together after being apart for a while.
Idea 1: "My (friends, classmates, teammates, or family members) and I all have a goal to (do something), and that goal unites us."
Idea 2: "If everyone (in some group or place) united, then together, we could (do something amazing, or fix a huge problem)."
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