( Monitoring heart patients' exercise as well as athletes excersing, is now done by small transmitters broadcasting physiological measurements to nearby recording machines. ) A. Monitoring heart patients' exercise as well as athletes excersing, is now done by small transmitters broadcasting physiological measurements to nearby recording machines. B. Monitoring the exercise of heart patients, as well as athletes excersing, is now done by small transmitters broadcasting physiological measurements to nearby recording machines. C. Small transmitters broadcasting physiological measurement to nearby recording machines are now used to monitor the exercise of both heart patients and athletes. D. Broadcasting physiological measurements to nearby recording machines, small transmitters are now used to monitor heart patients' exercise, as well as athletes exercising. E. Both athletes exercising and heart patients' exercise are now monitored by small transmitters broadcasting physiological measurements to nearby recording machines. 答案是C，错选了E。排除C的原因是感觉主语很长，头重脚轻。第一遍看原文的时候感觉exercise和exercising不平行，但是每个选项读下来发现都是这个形式，（当时没有注意到C的形式）于是就认为这个可能不是考点。E的错误是exercise和exercising吗？麻烦老师讲解。

请问这道题c选项为什么不能用过去完成式？之前的“had installed”不也是过去完成式吗...怎么判断什么时候用过去完成时什么时候用现在完成时什么时间用一般过去时啊？

请问这道题e选项“that”表示了什么？

请问在这道题里面 to do和doing的区别是什么？

请问这道题为什么不可以用过去完成时？“its trunk”里面的its会不会被当成是aquatic animal而不是大象？“with”之后是不可以接整句吗？

请问这道题b、c为什么不对

请问这道题e选项错在哪里？

请问这道题为什么不能选e？

请问为什么c不对？that of是什么意思？

请问in which 和 where的区别是什么？哪个能指代抽象地点，哪个是实际地点？

D选项错的原因之一是说不应该用that they participate 请问这个错在哪里了？