Of course, the worst case is to fall back to using threads for blocking actions that really cannot be converted into asynchronous callbacks.

当然，最坏的情形是回退到使用线程来进行阻塞操作，因为这些操作确实无法转换成异步回调。

youdao

The general goal is to keep the code inside the asynchronous callbacks as simple as possible and as disconnected from each other as possible.

总体目标是尽可能简单地将代码保存在异步回调中并且尽可能使彼此断开连接。

youdao

Alas it is also well known that asynchronous techniques require an inelegant or downright clumsy series of callbacks.

但同时大家也都知道异步技术要求一系列笨重的回调。

youdao