inner opposite angle

例句：

1. 1. The inner workings of the machine are quite complex.
   这台机器的内部构造相当复杂。
2. 2. She kept her inner feelings hidden from everyone.
   她把内心的感受隐藏了起来，不让任何人知道。
3. 3. The book's inner meaning is not immediately apparent.
   这本书的内在意义并不立即显而易见。