预先交给对方作为保证的钱

academic, literate, pandit, letters, litterateur, learned person, literati, philomath, pundit, academician, faculty member, scholar, bookman, clerk, student, scholarly person, man of letters, man of learning, speleologist, doctor, clerisy, initiate, swami, punditry, savant, learned man, sophist

duck, male prostitute (slang)

adj. (神情、气氛等) 使人感到敬畏的, (of expression, atmosphere, etc.) stern, grave, keeping a straight face; 严格的，认真的, strict, earnest

study, area, school subject, science, subject field, subject, course, subject area, discipline, branch of learning, course of study, field of study, branch of knowledge, field

graduate_school, research institute, school, laboratory, graduate school, institute