1. 表现
    The way that you behave is the way that you do and say things, and the things that you do and say.

    e.g. I couldn't believe these people were behaving in this way...
           我难以相信这些人竟会有这种举动。
    e.g. He'd behaved badly.
           他表现得很糟糕。

2. 守规矩；举止得体；行为检点
    If you behave or behave yourself, you act in the way that people think is correct and proper.

    e.g. You have to behave...
           你得规矩点。
    e.g. They were expected to behave themselves.
           他们应该守规矩。

3. （在科学领域）运动，起作用，作出反应
    In science, the way that something behaves is the things that it does.

    e.g. Under certain conditions, electrons can behave like waves rather than particles.
           在一定条件下，电子可以作波状运动，而不是粒子状运动。