Semi-submersible

A semi-submersible is a special kind of boat that is able to go partly underwater. It's kind of like a regular boat that has two big legs which stick out of the water, kind of like the legs of a table. These legs help the boat stay stable and not tip over.

The part of the boat that you can see above the water is called the deck. This is where the people on the boat can stand and work. The part of the boat that goes underwater is called the hull. This is where the engines and other important parts of the boat are.

Semi-submersibles are often used by scientists to explore the ocean and study marine life. They are also used by the military for things like surveillance and reconnaissance. But they can also be used for fun activities like fishing or diving.

So think of it like a special boat that can go underwater but still have a place for people to stand and work above the water too. It's kind of like a two-in-one boat!