Diffusion mixes things very well, but as the size gets bigger, diffusion becomes very slow.

扩散作用使物质充分混合,但随着细胞变大后,扩散作用就捉襟见肘了

耶鲁公开课 - 生物医学工程探索课程节选

it's a two-and-a-half-year-long program that mixes biology, chemistry, physics and computer science together.

这门课是一个两年半的项目，涵盖了生物学、化学、物理学，还有计算机科学。

与教授的面谈 - SpeakingMax英语口语达人