They began to categorize the particles' size, variation in size, and structure.

现在他们开始尝试对颗粒的大小、尺寸和结构进行分类。

youdao

They began to categorize the particles' size, variation in size, and structure.

现在他们开始尝试对颗粒的大小、尺寸和结构进行分类。

youdao