Match the phrase to its correct category. is the phrase an idiom or an euphemism? my car isn't used; it's preowned! my uncle has spent some time at a correctional facility. i've been studying for ten hours straight. i think i'll call it a day my grandmother gave up the ghost last night. the funeral is on saturday. i thought the sat would be hard, but it was really a piece of cake.                                        1. euphemism 2. idiom

Euphemism refers to a polite expression that is used in place of words that are otherwise considered harsh or unpleasant. The following statements are euphemism;
1. My car is not used, it is pre-owned.
2. My uncle has spent sometimes at a correctional facility. 
An idiom is a group of words which have been established by usage as having a meaning which is not deducible from those of the individual words. 
The following statements are idioms:
1.I have been study for ten hours straight, I think I will call it a day.
2. My grandmother gave up the ghost last night. The funeral is on Saturday.
3. I thought the SAT would be hard, but it was really a piece of cake.