1、At a guess I should say there were fifty people present
我估計有50人出席。

2、At a guess I should say there were fifty people present.
我估計有50人出席。

3、At a guess I shall say we are speed at fifty miles an hour
我猜測我們正以每小時五十公里的速度在前進。

4、At a guess he's been dead for two days.
據猜測，他已經死了兩天了。

at a guess翻譯