influence影响可数吗

The influence of climate on crops are self-evident.

气候对农作物的影响是不证自明的'。（不可数）

What are the influences of TV ads on us?

电视广告对我们的影响是什么？（可数）

News media have a  great influence on people's mind.

新闻媒介对人的思想有很大的影响。

I don't want to influence you. You must decide for yourself.

我不想影响你。你必须自行决定。