✅ Cheap describes something that doesn’t cost very much or costs less than expected (The coffee was cheap but hot).

✅ Economical describes something that is a good value, especially if it avoids waste (The recipe made economical use of expensive ingredients).

✅ Both of these terms tend to describe things that don’t cost very much.

✅ Economical suggests something that is a good use of money, whereas cheap suggests something that costs very little and can be of little value (The cheap necklace broke when he put it on).

✅ Interrogate means to question somebody, especially formally (I interrogated him about my missing cookies).

✅ Grill means to interrogate someone in a particularly persistent and intense way (I was grilled for ten minutes about my role in the grand cookie heist).

✅ Both of these words mean to question someone. Both usually suggest a formal interview, such as by the police, but both can also be used jokingly in everyday speech.

✅ Unique describes something that is the only one of its kind. Unique can also describe something uncommon or unusual (a unique approach; a unique bracelet).

✅ Rare describes something that is uncommon or unusual, especially something that is valuable (a rare mineral; a rare find).

✅ Both of these words describe unusual things, especially when being unusual makes them valuable.