如果你回想一下，你可能记得我从未答应要去。

If you ___cast ___your ___mind ___back, you might recall that I never promised to go.

因此，当我捡起这些石头中的一块时，我回想起找到它的具体地点、当时的我、那个特定的时刻。

Thus, when I pick one of these stones, I ___cast ___my ___mind ___back to the specific place where I found it, the person I was, the particular moment.

要完全理解这个问题，回想一下我们去年最初的讨论。

To fully understand the issue, ___cast ___your ___mind ___back to the original discussion we had last year.