导火索: fuse (for explosive)...
概况: general situation, summary...
精益求精: to perfect sth that is already outstanding (idiom); constantly improving...
上学: to go to school, to attend school...
大约: approximately, probably...
重申: to reaffirm, to reiterate...
青: green, blue, black, youth, young (of people)...
碳: carbon (chemistry)...
