求问以下句子 that it would otherwise....做什么成分，是什么从句。

It must be the case that an event, because it has a certain mental property (e.g., being a desire for a drink of water), enters into a causal relation (e.g., it causes you to look for a water fountain) that it would otherwise not have entered into.

Mental property 心理属性：感知觉，情感，欲望等都是心理属性。

causal relation 因果链，心理属性导致某个行为的因果。