Here are a few possibilities:
* Monkeys swing in the trees. Perhaps the answer is something like "Swing in the trees" or "Play in the jungle."
* Monkeys eat. Maybe the answer relates to their diet, like "Eat fruit" or "Have a snack."
* Monkeys are active. The answer could be something about their activity level, like "Get active" or "Explore."
Can you give me more clues to help me figure out the answer?