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[Big Frank]

I could not accomplish that, I have still a problem, with the other directions, I have created a rectangle, clicked on the curve,so I have four rounded corners, I like to make the bottom two corners square again, I click on, and click on delete corner,the whole square goes away, or how do I select the corner and convert them ? and select the converted ?

It was quicker to do this than to do a detailed tutorial on what are two fairly basic operations combined into one artistic feature