被动控制系统是利用自然环境力矩源或物理力矩源来控制航天器姿态，其不需要能源、姿态敏感器和控制逻辑线路。
查看答案
The police respond ______ emergencies in just a few minutes.
She often complains ______ not feeling appreciated at work.
Families should stick together ______ thick and thin no matter what happens.
Your life changes ______ when you have a baby. （dramatic, dramatically)
微信支付 
支付宝支付