Treatments for animals developed using animal testing include pacemakers for heart disease and hip dysplasia. animals后面为什么既有过去分词又有现在分词?过去分词和现在分词可以同时出现修饰一个单词吗?还有别的例子吗
...ur spare time, playing cards at home or taking a walk in the park?我知道可以填 to spend 构成目的状语。但我的另一个理解是 enjoy spending your spare time (in) which. which 代指 playing cards at home or taking a walk in the park 作(in) 的宾语。翻译成中文:你更享受...