Intensionality is like when you see a picture of a dog and you know it's a dog, even if someone else might call it something else or think it's a different animal. It's about what you mean or think about something, and not just the thing itself.
For example, if you say "I want a fruit that's red and round," someone else might bring you an apple, but you might actually be thinking of a tomato. This is because when you said "fruit," you had a certain idea or meaning in your head, and that's what intensionality is all about - the meaning behind words or ideas.
In simpler terms, intensionality is like the thoughts and ideas we have in our minds when we use words, and not just the actual things or objects themselves.