音标: 英 [pri:'ɒpәrәtiv]
1. After arrival, your preoperational training will continue as normal.
到达后 你们的行动前训练 将如常继续
2. We could manage clotting risk preoperatively with an infusion of unfractionated heparin.
可以通过注射普通肝素 在术前控制住血栓风险
3. The sensorimotor stage, the preoperational stage, the concrete operational stage, and the formal operational stage.
感觉运动阶段 前运算阶段 具体运算阶段 以及形式运算阶段