A lot of language learning ,_______has been discovered, is happening in the first year of life, so parents should talk much to their children during that period .
第二部分:英语知识运用(共两节,满分45分)
第一节:单项选择(共15小题;每小题1分, 满分15分)
21.The experiment turned out to be______ failure, but as we know, Success often comes after_____ failure.