起初我们着手研究的是看起来似乎最简单和最明显的滤波器.We started with what seemed the most simple and obvious filter.在适当条件下,多层膜还可作滤波器.Under appropriate conditions a multilayer may also be employed as a filter.这个信号送到滤波器 - 放大器,它是由变压器耦合到视频检波器的.The si...
Several German states have banned teachers from wearing the headscarf.德国也有若干州禁止教师这么做.She pushed all her hair under a headscarf.她把头发都让头巾罩住.A long thin wool coat and a purple headscarf protected her against the wind.一件薄薄的羊...