(located) at; (to be) in; to exist; in the middle of doing sth; (indicating an action in progress)[cedict]
一
yīㄧ
one; 1; single; a (article); as soon as; entire; whole; all; throughout[cedict]
次
cìㄘˋ
next in sequence; second; the second (day, time etc); secondary; vice-; sub-; infra-; inferior quality; substandard; order; sequence; hypo- (chem., meaning extra oxygen atom); classifier for enumerated events: time[cedict]
臥底
wò dǐㄨㄛˋ ㄉㄧˇ
to hide (as an undercover agent); an insider (in a gang of thieves); a mole[cedict]