It's the bit that's left when you take the solid lumpy buttery bits out of the milk.

是牛奶凝结成块状时留下的少量部分。

" Yes, it is a solid bit of work" .

“是的，这是一项扎实的工作”。

The stuff coating a film strip is technically closer to a suspension, which has tiny solid bits floating around in a fluid.

严格来说，涂在胶卷上的物质更接近于漂浮着许多微小固体颗粒的悬浮液。