Keratoelastin
鱼卵壳蛋白
🗣️ 情景例句
You haven't answered my question.
你还没有回答我的问题呢。
His finger is wounded, Does it hurt?
他的手指受伤了，疼不疼？
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。