6. What is a critical period?

innate "time-window" in development for learning certain skills
genetically determined "time-window" in development for learning certain skills
environmentally determined "time-window" in development for learning certain skills

7. What is the problem of invariance?

speech varies between speakers and there are differences in pitch, pronunciation, speed, and accent
speech varies between speakers and there are differences in tone, amount of words and accent
speech varies between speakers and there are similarities in pitch, pronunciation, speed, and accent
speech varies between speakers and there are differences in energy levels and physical states

ensure adults get the right experiences and remediation of any wrong kind of experience
ensure children get all experiences and remediation of any wrong kind of experience
ensure children get the right experiences and remediation of any wrong kind of experience
ensure children get all experiences and remediation of any right kind of experience

language learnt outside the critical period is acquired through different process or with difficulty
language learnt inside the critical period is acquired through different process or with difficulty
language learnt outside the critical period is acquired through the same process but with difficulty
language learnt outside the critical period is acquired through different process but with ease

individuals can attain full mastery of language if L1 is learned in sensetive period
individuals can attain partial mastery of language if L1 is learned in critical period
individuals can attain full mastery of language if L1 is learned in critical period
individuals will not attain full mastery of language if L1 is learned in critical period

pronunciation, production and comprehension of morphology & syntax, GJT, and working memory speed & accuracy
pronunciation, production and comprehension of semantic & lexical, GJT, and processing speed & accuracy
pronunciation, production and comprehension of morphology & syntax, GJT, and processing speed & accuracy
pronunciation, production and comprehension of morphology & syntax, GJR, and processing speed & accuracy

adjustments made to account for the variation in mental properties (emotion, beliefs & speed) across speakers
adjustments made to account for the variation in physical properties (phonomes, syllables & words) across speakers
adjustments made to account for the similarties in physical (phonomes, syllables & words) properties across speakers
adjustments made to account for the variation in physical properties (phonomes, syllables & words) across readers