我相信诚实，即使这很困难。

I ___believe ___in being honest, even when it's difficult.

我不相信一旦做出决定还应该改变主意。

I don't ___believe ___in changing my mind once I've made a decision.

她相信教育有改变人生的力量。

She ___believes ___in the power of education to change lives.