What are submersibles for?
Submersibles are small, hard-sided vehicles that can dive down deep. It has its own power and air supplies. Some parts of the ocean are way too deep for anyone to swim in, even with diving gear. People need submersibles to explore the deepest parts of the ocean.
Instruction: What are submersibles for?
Context: 
Response: Submersibles are small, hard-sided vehicles that can dive down deep. It has its own power and air supplies. Some parts of the ocean are way too deep for anyone to swim in, even with diving gear. People need submersibles to explore the deepest parts of the ocean.