请问各位老师,
Biber的
Spoken and written textual dimensions in English,
Variation across Speech and Writing,
Dimensions of Register Variation: A Cross-linguistic comparison和
Variation in English: Multi-Dimensional Studies 这四本书各自有什么侧重点?我想学习一下他的多维度分析方法(MDA),是不是这4本书都要看?谢谢