Hi there! Let's talk about the sentence: "A scan of the brain can show if a person is in love!"
The sentence is mostly correct, but we can make it a little clearer by saying: "A brain scan can show if a person is in love." This means scientists can look inside the brain using special machines to see what parts are active when someone is feeling happy and loving.
Isn't it amazing that our brain can tell us about our feelings? So yes, the sentence is correct, and we just improved it a bit to be clearer!