Osteoclast
破骨细胞
🏥 医学释义
折骨器
🗣️ 情景例句
What do you do in your spare time?
你在业余时间做什么？
Did you go to the store yesterday?
你昨天去商店了吗？
But here we come up against the most difficult of all obstacles to contact with people on other planets ----the astronomical distances which separate us.
然而，在和外星人联系中我们遇到的最大困难是分隔我们的天文距离。