1. （行为、观念等）传统的，符合习俗的
    Someone who is conventional has behaviour or opinions that are ordinary and normal.

    e.g. ...a respectable married woman with conventional opinions.
           一位观念传统、受人尊敬的已婚女性

2. （方法或产品）通常的，传统的
    A conventional method or product is one that is usually used or that has been in use for a long time.

    e.g. It is simpler and quicker to use than conventional methods.
           这比通常的做法更简单、更快捷。
    e.g. These discs hold more than 400 times as much information as a conventional computer floppy disk.
           这些光盘能容纳的信息量是普通计算机软盘的400多倍。

3. (武器、战争等)常规的，非核的
    Conventional weapons and wars do not involve nuclear explosives.

    e.g. We must reduce the danger of war by controlling nuclear, chemical and conventional arms.
           我们必须通过控制核武器、化学武器和常规武器的数量来减少战争的危险。

4. conventional wisdom -> see wisdom