n.咖啡因，茶精（一种兴奋剂）...

They appear appeal mainly to young people and are fueled mainly by caffein caffeine.他们主要受到年轻人的喜爱,而且原料主要是咖啡因....

caffein的音标：caffein的英式发音音标为：['kæfi:n]caffein的美式发音音标为：['kæfin]...