i thought i'd write to tell you about the American school system?中'd是谁的缩写,并解释原因,
问题描述：
i thought i'd write to tell you about the American school system?中'd是谁的缩写,并解释原因,
答
would
原因：句中谓语是thought 是think 的过去式 thought 之后的是从句,时态和thought 一致,故用其过去式would表将来
其他句型中 i‘d like to do sth.i would like to do sth.表虚拟,用will 的过去式would