Hxen.com's tips：Every day persisted can learn English well!-->■Learn English Everyday■
pre-emptive – adj. done to stop an unwanted act by another group or country from happening
fictitious – adj. not true or real
alert – n. to give (someone) important information about a possible problem or danger
response – n. an answer; something spoken, written or done in reaction to something else
isolate – v. to put or keep (someone or something) in a place or situation that is separate from others
