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tackle - v. to forcefully seize (someone) and cause that person to fall to the ground
alert - adj. able to think clearly and to notice things
lock - v. to fasten the door, lid, etc., of (something) with a lock
counter - v. to do something in defense or in response to something — often + with
evacuate - v. to remove (someone) from a dangerous place
confuse - v. to make (someone) uncertain or unable to understand something
grab - v. to quickly take and hold (someone or something) with your hand or arms
principal - n. the person in charge of a public school
barricade - v. to block (something) so that people or things cannot enter or leave
option - n. the opportunity or ability to choose something or to choose between two or more things
