短語詞組短語be e busy doing sth 忙于be kept busy doing sth 被迫忙于be busy doing sty 忙于做be busy doing sth 忙于做某事;忙于;忙于干某事;忙于做be busy doing detail 忙于做be busy doing stn 忙于做某事be busy doing something 忙于做某事;忙做;忙于做doing be busy doing sth 忙于干某事playing be busy doing sth 忙于做某事 返回 be busy doing