You know from experience if you've ever mixed them to make salad dressing, they don't mix too well. And you may know that if you heat them up, they mix much better.

经验告诉我们,你无法把它们混合做成色拉酱调料，他们不会很好的混合，但是你也知道,如果我们把他们加热，就能够混合的更好。

麻省理工公开课 - 热力学与动力学课程节选

And in two remaining areas, progress was too mixed to be characterized one way or the other.

NPR: White House Releases Iraq Report

Analysts, too, were mixed in their reactions to what Obama had to say Wednesday night.

CNN: State of the Union: Highlights, reactions, analyses

He suggested that bright students should be pushed as they would be if they attended independent or grammar schools, adding that too many were left to coast in mixed ability classes or entered too early for exams.

BBC: Top maths pupils 'fail to keep up with world's best'