Original proposition:

If x=3, then y=4 or y=5.

Inverse proposition:

If y=4 or y=5, x=3.

No proposition:

If x is not equal to 3, then y is not equal to 4 or y is not equal to 5.

Negative proposition:

If y is not equal to 4 or y is not equal to 5, then x is not equal to 3.

Therefore, the negative proposition of or is not sum. "Or" can't be an independent compound proposition, because compound propositions have negative propositions. The format of compound proposition is "If P is Q", its negative proposition is "If Q is P", its negative proposition is "If P is not Q" and its negative proposition is "If Q is not P".

"or" and "and" can only be contained in the p or q of the proposition without change.