英语语法分析

Tropism refers to the tropism that occurs when an organism is exposed to a stimulus.

向触性是指生物体接触到刺激时发生向性运动。

Aerotropism a tropism in which the orientating stimulus is oxygen.

向氧性：一种刺激方向为氧气的向性运动。

At last, I put forward the principle on implementing the value tropism.

本文最后提出了实施这一价值取向的原则要求。