Fish-able, I'm afraid that you seem to have misunderstood the question. I agree with bhaisahab that "in this slide" is preferable, but there's nothing wrong with saying "on this slide".It's not like that. It's about the appropriate preposition in the proper context. As you may say:
- Look at the slide.
- "In this slide" inside the slide.
- You really cracked me when you thought it's "On the slide".
If you have a question about the English language and would like to ask one of our many English teachers and language experts, please click the button below to let us know: