1. The heart performs a vital bodily function.
    心脏起著维持生命的重要作用.

2. They also play a vital role in helping parents understand the types of peer pressure their children experience.
    他们在帮助父母亲理解孩子们所经受的各种来自于同龄人的压力方面也起着重要作用。

3. Naoto's immediate goal is to pass the entrance examinations for a private junior high school, a vital step for eventual admission to a prestigious (有名望的) university.
    直仁眼下的目标，是想通过入学考试，进入一所私立初级中学——这是最终进入一所著名大学的关键一步。

4. Keeping up with the face-to-face class and completing all work on time is vital.
    一旦落后就很难追上。

5. Positive motivation — the gathering of feelings of enthusiasm, energy and confidence — is vital for achievement.
    积极的动机，即积聚起高涨的热情、旺盛的精力和充分的信心，这对获得成就至关重要。