中古藏语具有yin、lags和red三个系动词,同时它们还兼做助动词。red至迟不晚于14世纪语法化为系动词,它打破了古藏语yin和lags表“统称~敬称”的平衡,而使藏语逐步过渡到yin和red表“向自我~向他者”示证范畴的对立。 Middle Tibetan has yin, lags and red three lines of verbs, at the same time they also serve as auxiliary verbs. red no later than the grammaticalization of the 14th century as a system verb, which breaks the balance between the ancient Tibetan language yin and the lags table “collectively referred to ” and makes the Tibetan language gradually transition to the yin and red tables Opposition to the category of “others”.