Water Cycle — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. Water from lakes goes up as vapor.
Sunlight warms the lake, and the warm water rises into the air as vapor, which is water in the form of a gas.
2. Vapor rises and forms a cloud.
As vapor floats higher, it cools down and joins with other tiny drops to form a cloud in the sky.
3. Heavy clouds drop rain to the ground.
Once a cloud collects too many water drops to hold, it grows heavy and lets the drops fall as rain.
4. Rain flows into rivers and lakes.
After rain hits the ground, the water flows downhill and gathers in low places like rivers and lakes.
5. The sun heats the water to start the cycle.
The sun's heat is what gets everything moving by warming the water so it can rise into the air.
6. Water keeps moving in a cycle.
Water moves from the ground to the sky and back again over and over, so this repeating path is called a cycle.
7. Puddles dry up because of the sun.
Sunlight heats the puddle until the water turns to vapor and floats away into the air, which makes the puddle disappear.
8. Cold air turns vapor back into water drops.
When vapor meets cold air high in the sky, it cools and changes back into tiny water drops.
9. A river carries rainwater to the ocean.
Rivers carry rainwater across the land and finally empty it into the ocean.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
rain
→ water falling from sky
water falling from sky
vapor
→ water turned to gas
water turned to gas
cloud
→ fluffy shape in sky
fluffy shape in sky
cycle
→ goes round and round
goes round and round
Rain is water falling from the sky, vapor is water that has turned into a gas, a cloud is the fluffy shape made of water drops in the sky, and a cycle is something that goes round and round.