secretly

ad. 秘密地,背地里

seconder, secondhand, secondly, secondment, secrecy, secrecy (title), secret, secret agent (also agent), secret police, secret service, secretarial, secretariat, secretary, Secretary of State, Secretary-General, secrete, secretion, secretive, secretively, secretiveness, sect, sectarian, sectarianism, section, sectional, sectionalism, sector, secular, secularism, secularist, secularize, secularise, secure, securely, securities, security, security guard, security risk, sedan, sedate, sedately,