In the ted talk “The linguistic genius of babies” by Patricia Kuhl (2010), she points that babies and children are genius language leaners because their brain is different. The topic starts with a graph, it shows people have a “critical period” of acquiring a second language until 7-year-old, then it turns decline gradually until age of puberty. She studied about how do babies find sounds of different language in the first “critical period”. She did two tests about babies under 1-year-old listening different language — American English, Japanese, and Mandarin. The results show that babies between 8 months to 12 have high sensibility on sounds of languages which they listened for some time, even a brand new language. Kuhl describes babies
