There are 7 days in a week and 2 cups are recommended per day, bringing the total to 7 days * 2 cups/day =<<7*2=14>>14 cups for the week.
Out of the 14 total cups needed for the week, Sarah has already eaten 8, for a total of 14 cups - 8 cups = <<14-8=6>>6 cups left to consume for the week.
Sunday through Thursday equals 5 days that have passed. If there are 7 days in the week then Sarah has 7 days - 5 days = <<7-5=2>>2 days left of the week.
If she needs to eat 6 more cups in the next 2 days then she will have to eat 6 cups / 2 days = <<6/2=3>>3 cups per day over the next two days.
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