小男孩飞快的向母亲跑去 The little boy ran to his mother_____ _____ _____ _____ _____.

as adj as one can = as adj as possible
飞快的跑去as quickly as he could
The little boy ran to his mother as quickly as he could
=The little boy ran to his mother as quickly as possible
不明白的再问哟,请及时采纳,多谢!