With time case as the object and 1 million Mandarin words as the base, the research aims at sorting out the NPK subcategories in time case and working out the frequency of time prepositions.

• 通过对时间格的研究,在100万汉语普通话语料的基础上,梳理出时间格后NPk的次范畴种类,统计出现代汉语中各时间格的介词的使用频率。