Most adults spend the day in damp, shady areas where they can find protection from the sun; some of them will even hide in your house. Mosquitoes need water to lay their eggs in and plants to hide in so they are usually found around water and plants. Mosquito eggs are laid on water or damp soil where the young mosquitoes grow and develop.
Different mosquitoes prefer different kinds of water. Some like swamps or ponds and others prefer water in swimming and wading pools, old tires, watering cans, flower pots, trash cans, etc. When the young mosquito turns into an adult, it leaves the water and flies away.