Language attrition (1)aphasia

The target people are those who lived more than 4 years in America. He divided the people into 4 groups; (ⅰ)the children in the lower grades of elementary school after 1 year,(ⅱ) children in the lower grades of elementary school after 2 years, (ⅲ) children in higher-grades of elementary school after1 year, (ⅳ) the people are children in ... ................
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