单词	extended value
释义	extended value短语²⁴⁶⁹⁹扩充值
随便看	second language acquisition theory Second Language Acquisltion second language acquistion second language and foreign language Second Language Aquisition second language attrition second language classroom second language culture second language ego second language instruction second language learner second language learners second language learning second-language learning second language learning of adults second language learning strategies Second language learning Strategy second language lexical ability second language lexical acquisition Second Language Listeners second language oral test second language reading second language research Second Languages second language teacher