protagonist n. 主角
- Brutus is the protagonist in William Shakespeare's JULIUS CAESAR, and Antony is the antagonist.
protocol n. 1. 草约 2. （外交等的）礼节
- The protocol initiated by the representatives of the three nations is expected to lead to a formal treaty.
- It is a breach of protocol for a subordinate publicly to question the judgment of his superior officer.
protoplasm n. 原生质
- Protoplasm distinguishes living from nonliving things.
prototype n. 原型
- The crude craft in which the Wright brothers made the first successful flight in 1903 was the prototype of the modern airplane.
protozoan n. 原生动物
- The tiny protozoans are believed to be the first animals to have appeared on earth.