Most of my friends didn't go to the movie. John is one of my friends. So John didn't go to the movie. All of the students on the Dean's List have a GPA of 3.5 or better. Some English majors are on the Dean's List, so some English majors must not have have a GPA of 3.5 or better.
Some mushrooms are expensive.
Potato chips are not expensive. So some mushrooms are not potato chips. My company is laying off some of its best workers. I don't work for a good company. Therefore, a good company doesn't lay off some of its best workers.