* They are all irregular verbs. This means they don't follow the standard rules for forming past tense and past participles.
* Fit: Present tense - fit, Past tense - fit, Past participle - fit
* Set: Present tense - set, Past tense - set, Past participle - set
* Read: Present tense - read, Past tense - read, Past participle - read
* They are all common verbs in the English language. They are frequently used in everyday speech and writing.
Let me know if you'd like to explore other similarities or if you have any other questions about these words!