他的演说很难听懂，他的签名颤颤巍巍地无法识别。His speech was difficult to understand, his signature shaky and unrecognizable.他灵巧的动手能力和杰出的空间识别能力都浪费在日常事务上了。His manual dexterity and fine spatial skills were wasted on routine tasks.我很快就学会了识别牌照前面的代...
欧洲的交流电输出频率通常为50赫兹。In Europe, AC is usually generated at 50 Hz.你可在短波37.5赫兹上收到我们的节目.You can receive our program at short wave 37.5 MH.频率用赫兹即每秒钟的周数来计算.Frequency is measured in hertz, or cycles per second....