occasionaladj.偶然的;临时的;不时的
occasional specie偶见种
occasional verses应景诗
occasional visits偶尔看望
occasional victim偶然被害人
occasional papers不定期论文
occasional driver临时驾驶员
occasional survey偶然调查
occasional connect偶尔连接
occasional enquiry偶尔询购
occasional neglect偶尔的疏忽