向可再生能源的过渡是一个渐进的过程。

The transition to renewable energy is a ___gradual process.

我注意到我的英语口语能力在逐步提高。

I've noticed a ___gradual improvement in my English speaking skills.

整个星期，气温在逐渐上升。

There was a ___gradual rise in temperatures throughout the week.