英汉词典

1. 有根据的;正当的;合理的
    A valid argument, comment, or idea is based on sensible reasoning.

    e.g. They put forward many valid reasons for not exporting...
           他们提出了很多不出口的正当理由。
    e.g. It is valid to consider memory the oldest mental skill, from which all others derive...
           我们有理由认为记忆是最原始的心智技能，所有其他技能都在此基础上衍生出来。