Exercise 3: Write the words in the correct blanks.
Exploring the Sea by Submarine
1. Submarines travel to the Answer parts of our oceans.
2. They help scientists understand the Answer of the sea.
3. Because oceans Answer a lot of Earth, there is a lot to explore.
4. Not all submarines are the same. There is a Answer of types.
5. The fastest Answer can travel around 40 miles per hour.
6. Some submarines can Answer their journeys without anyone on board.
7. At the Answer of each trip, scientists make sure their submarine is in good condition.
8. Scientists must be healthy. If they have an Answer, they cannot travel on a deep sea mission.