1. 坚定的信念(或主张)
    A conviction is a strong belief or opinion.

    e.g. It is our firm conviction that a step forward has been taken...
           我们坚信已经向前迈进了一步。
    e.g. Their religious convictions prevented them from taking up arms.
           由于宗教信仰的原因，他们不会拿起武器进行反抗。

2. 坚信;深信;确信
    If you have conviction, you have great confidence in your beliefs or opinions.

    e.g. 'We shall, sir,' said Thorne, with conviction.
           “我们会的，先生，”索恩坚定地说。

3. 令人信服;有说服力
    If something carries conviction, it is likely to be true or likely to be believed.

    e.g. Nor did his denial carry conviction.
           他的否认也没有说服力。

4. 定罪;判罪
    If someone has a conviction, they have been found guilty of a crime in a court of law.

    e.g. He will appeal against his conviction...
           他会对判决提起上诉。
    e.g. The man was known to the police because of previous convictions.
           因为有犯罪前科，警察们都认识这个人。