Some people wash/change them often - like once a week. Others every couple weeks, maybe 3-4. For some people maybe more often.. and some people almost never wash or change their sheets and they get REALLY disgusting. I know a smoker that's like this and I think one of the reasons is because he smokes and can't smell very well and doesn't realize his bedsheets are as dirty as they are.
I tend to wash mine every few weeks-ish. Sometimes a little more often in the Summer if I sweat a bit more, or if I Know I was too exhausted to bother showering went to bed a little dirty. Basically, I wash them whenever they need to be washed and never let them get gross.. because that's gross. Who would want to sleep on diiiiirrrtyyy sheets? Not me!
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No
for supporting trump. Because doing so is deplorable.