打擾大伙了，我想問一下this和that是不同，這是在我做一道英語填空題的時候發現自己搞不懂this和that有什么區別，對此我糾結了很長時間。題目如下：

All decisions about who did what, how quickly and by when, were the responsibility of the whole group. It was found that groups of this type became very committed to the task and produced high-quality work.

我記得that是將上文的事，而this是指下文的事，所以我填了that，但答案是this，請大伙幫忙剖析。

that不能指代下文才提及的事情，但this則既能夠指代前文的事，也可以指代下文才出現的事，并不是只能指代下文。

當說話人只提及一件事時，指示代詞用近指代詞this。比如：

I bought a book yesterday. This book is interesting. 而不是that book.

當說話人提及二個事物，后提及的事物用遠指代詞that指代。

The book you lent to me is easier to read than the one I borrowed from Tom. That book is not suitablefor me.