[译] 氧、二氧化碳、氮是动植物生命所必需的。
[误] Oxygen, carbon dioxide, and nitrogen are essential for animal and plant life.

[正] Oxygen, carbon dioxide, and nitrogen are essential to animal and plant life.
[注] 形容词 essential 之后加介词 to 表示“（对……来说是）必需的”，又如：The atmosphere is essential to communications. 大气对通讯十分重要。