Hxen.com's tips：Every day persisted can learn English well!-->■Learn English Everyday■
reward – n. a prize given in recognition of one's effort or service
unlocked – adj. related to something that is undone or open
key – n. an instrument that is used to start up an automobile
sticker – n. something that sticks to a person or an object; a notice
sheriff – n. an elected officer who is responsible for keeping the peace
smash – v. to break (something) into many pieces; to shatter or destroy (something)
grab – v. to quickly take and hold (someone or something) with your hand or arms
desperate – adj. feeling or showing a sense of hopelessness
patrol – n. a person sent to keep watch over an area
statistic – n. a fact or piece of information from a large study
