相關(guān)單詞近義詞 underground 地下的, secretively 穩(wěn)秘地, stealthily 暗地里, secretly 秘密地, slyly 狡猾的, surreptitiously 偷偷摸摸地, on the sly 秘密地臨近詞furtive 返回 furtively