I like to dip them in ketchup.
Meaning: This sentence describes a preferred method of eating hotdogs.
Choice of Words: Dip means to put something briefly into a liquid. Them refers to hotdogs. Ketchup is a tomato sauce. When you put them together, "I like to dip them in ketchup" means that you enjoy briefly submerging hotdogs in ketchup before eating them.
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Related Expressions