Fraser C, Roberts N
J Psycholinguist Res. 1975 Jan;4(1):9-16. doi: 10.1007/BF01066986.
This study reports analyses, in terms of five different measures, of the speech on two standard tasks of 32 middle-class mothers to their children aged 1 1/2, 2 1/2, 4, and 6 years. Sex and birth order of child were not found to be related to mothers' speech. On four of the measures, both task and age of child had strongly significant effects. In general, with increasing age of child, mothers spoke more, in longer and grammatically more complex utterances, with greater diversity of vocabulary. The differences in speech addressed to 1 1/2-year-olds and that addressed to 2 1/2-year-olds were particularly marked.
本研究报告了对32位中产阶级母亲针对1岁半、2岁半、4岁和6岁孩子在两项标准任务中讲话的分析，分析采用了五种不同的测量方法。未发现孩子的性别和出生顺序与母亲的讲话存在关联。在其中四项测量方法中，任务和孩子的年龄都有非常显著的影响。总体而言，随着孩子年龄的增长，母亲讲话更多，句子更长且语法更复杂，词汇也更加多样。针对1岁半孩子和2岁半孩子的讲话差异尤为明显。
