ocr: "That" or "Which" IF the marked group of words - is essential to the meaning of your sentence, use "that" to introduce the group of words. Do not use a LUlliiid. IF these words are not essential to the meaning of your sentence, use "which" and separate the words with a comma. - - Instead of: Did you learn the dance, that is from auatemalar Consider: Did you learn the dance, which is From quatemala? Or consider: Did you learn the dance that is from auatemalar J Instead of: We want to buy the photo which Harry took. C Consider: We want to buy the photo, which Harry took. Or consider: We want to ...