Sampleite
氯磷钠铜矿
🗣️ 情景例句
How much do stamps cost?
邮票多少钱？
I'm sorry. Am I keeping you awake?
对不起。我吵得你睡不着了吗？
and if a single curved glass would distort nature, how much more would a pair of them?
何况一片曲面镜就可歪曲自然，那么伽利略的两片曲面镜对自然的歪曲又该多大呢？