Good job! Your sentence is mostly correct. Here it is:
A ray hides in the sand, with just its eyes popping up to spy the ocean.
Step-by-step (easy words):
- "A ray" — the subject (a ray is a kind of fish).
- "hides" — the action (it matches the single ray).
- "in the sand" — tells where it hides.
- "with just its eyes popping up to spy the ocean" — extra information about how it hides.
- "its" is correct (not "it's"). "Just" means "only." "Spy" means "watch quietly" — you can use a simpler word if you like.
- The comma before "with" is okay but not needed. You can leave it out for a simpler sentence.
Two simple, kid-friendly versions you can use:
- A ray hides in the sand with only its eyes poking up to watch the ocean.
- A ray hides in the sand; only its eyes peek out to watch the ocean.
Both are correct — pick the one you like best!