surreptitious

adj. 鬼鬼祟祟的，保密的

surly, surmise, surmount, surmountable, surname, surnamed, surpass, surpassing, surpassingly, surplice, surplus, surprise, surprised, surprising, surprisingly, surreal, surrealism, surrealist, surrealistic, surrender, surreptitiously, surrey, surrogate, surround, surrounding, surroundings, surtax, surveillance, survey, surveyor, survival, survive, surviving, survivor, sus (also suss), susceptibility, susceptible, suspect, suspect sb. of, suspend,