Just try to stay calm. Most people do worse just because they let the idea of the ACT get to them. Study if you feel you need to (suggest using the practice tests on the collegeboard site), but don't go overboard.
I know people who have taken classes entirely devoted to conquering the ACT. They almost always do very poorly, at least on their first try.
And remember, you can always try again.
English
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But only minor, like on the leg or in the parents
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But here in north Korea, you get shot if you get a failing grade