多选题The formal instruction in second language acquisition has no effect at all. （ ）多选题The optimum age for second language acquisition is after puberty. （ ）多选题L1 development and L2 development involve the same processes. （ ）多选题Interlingual errors can be found at other levels such as lexical, grammatical or discoursal. （ ）多选题According to contrastive analysis, the greater the difference between L1 and L2, the more errors that will occur. （ ）多选题Second language acquisition refers to the systematic study of how one person acquires an L2 subsequent to his native language. （ ）多选题Negative transfer will interfere with or hinder target language learning. （ ）多选题L1 is acquired subconsciously, while L2 or FL is learned consciously. （ ）