Relier Pairs Brown’s MLU stagesVersion en ligne Test yourself on Brown’s research on morphological acquisition by matching pairs of morphemes with the month age of mastery. par Som Person 1 Regular past 2 Regular third person 3 Possessive ‘s’ 4 Present progressive 5 Irregular past 6 Regular plural 28-50 19-28 26-40 25-46 27-33 26-48 1 Early I 2 Late II 3 Early III 4 Late I 5 Early II 6 Late III 12-22 28-30 31-32 27-28 33-34 22-26