她是环境保护的坚定倡导者。

She is a strong ___advocate for environmental protection.

许多可再生能源的倡导者认为它对未来至关重要。

Many ___advocates of renewable energy believe it's essential for the future.

作为言论自由的倡导者，他捍卫每个人表达意见的权利。

As an ___advocate of free speech, he defends everyone's right to express their opinions.