1. Outside/Inside: SIMPLE ANTONYMS

(a) The kids played outside.

(b) The kids played inside.

There is no middle ground for these antonyms. The kids can’t play half outside, or kind of inside. It is one or the other. They are either outside or inside.

2. Expensive/Cheap: GRADABLE ANTONYMS

(a) The concert tickets were expensive.

(b) The concert tickets were cheap.

These are words that can be put on a scale. They are not binary in that neither of these sentences have to be true. The tickets could’ve either been expensive, cheap, or reasonably priced making neither sentence true. The tickets could’ve also been extremely cheap or kind of expensive. There is a lot of gray area making these gradable antonyms.

3. Lower/Raise: REVERSES

(a) Jane lowered the volume on the radio.

(b) Mark raised the volume on the radio.

These are reverse pairs because they indicate opposite directions of motion. The force is being applied on the same scale of volume in either direction. Whether it is being raised or lowered.

4. Student/Teacher : CONVERSES

(a) Prof. Pentangelo is the teacher of Kristin.

(b) Kristin is the student of Prof. Pentangelo.

These sentences mutually entail each other and are a paraphrase of one another. If it is true that Prof. Pentangelo is Kristin’s teacher, then obviously Kristin must be their student.

5. Rose/Orchid: TAXONOMIC SISTERS

(a) Rose is a kind of flower.

(b) Orchid is a kind of flower.

Rose and Orchid are 2 hyponyms that belong to the same hyperonym of flower. This makes them taxonomic sisters because they are 2 things that lie under the same category.