Paragraph (With Errors)
He speaked quietly as he walked down the street, careful to not to disturb anyone. Suddenly, he realized he forget his keys at home. Quickly, he turned around and runned back to get them.
Paragraph (Corrected)
He spoke quietly as he walked down the street, careful not to disturb anyone. Suddenly, he realized he forgot his keys at home. Quickly, he turned around and ran back to get them.