Sems
(sem 的复数) abbr. 标准电子组件（Standard Electronic Modules）；扫瞄式电子显微镜（scanning electron microscope）
🗣️ 情景例句
I had never been there before.
我以前从来没有去过那里 。
I think a joint venture would be beneficial to us both.
我认为合资经营对双方都是有利的。
Now move the hand to and fro and around but not up and down.
然后把手前后左右以及旋转摆动，但不要上下摆动。