There are many examples you could go with, but one is "If a shape is a square, then it is always a rectangle".
The converse has us flip the statement into "If a shape is a rectangle, then it is always a square" which is not true. Some rectangles aren't squares.
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Another example could be "If it is a dog, then it is an animal" which is always true. The flip of it is "If it's an animal, then its a dog" which is false because the animal could be a cat for instance.
