a signal is fed back to the input and combined with the input signal to produce a desired system response.fed 和combined 应该都是被动语态,,可是只用了一个be动词,这在语法上是合理的吗?谢谢老师!
The
president was reported to have been flying across the Atlantic.这句话和The
president was reported to be flying across the Atlantic.含义有区别吗?怎么样理解二者的含义差别呢?
One such idea is that fish is the best brain food. Fish is good brain food just as it is good muscle food and skin food and bone food. 这里面的as为什么不可以填because呢?
阅读题里的一句:_____ his research, Pearson(人名) is able to put dates to most of the breakthroughs that can be predicted.选through 还是 by,当表示“通过、凭借、由于(某种方式,手段)”时他们的用法区别是什么?望老师不吝赐教!谢谢!!
阅读题里的一句:_____ his research, Pearson(人名) is able to put dates to most of the breakthroughs that can be predicted.选through 还是 by,当表示“通过、凭借、由于(某种方式,手段)”时他们的用法区别是什么?望老师不吝赐教!谢谢!!