Take blames/Take the blame?
I know we say "I'm not TAKING THE BLAME for that." Here it's talking about a single incident/blame. But if I want to talk about several incidents do I say 'TAKE BLAMES,' for example:
"You have to take blames for your mistakes"

Question

Answer

Blame is a noun, is an uncountable noun. So as Josh has written, it can get an S when you use He or She with it.
In the sentence" I'll take the blame", something has gone wrong! Right? Why something has gone wrong? Because of some mistakeS. But the person says "Blame" and doesn't say "I'll take the blames"

Answer

Blames would only be used when you say "he/she blames me for what happened" 
'Blame' itself typically only refers to one incident.
For multiple incidents I would use "own up to your mistakes" or "take responsibility for your mistakes"

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