1.当我把盐买来时,我发现盐有点脏.
When I bought the salt,I found it to be slightly dirty.
After having bought the salt,I found it to be a bit dirty.
（Dirty 可以用 unclean 来代替）
2.这时,奇怪的事发生了：我的盐消失了.
At this moment,a strange thing happened:My salt vanished.
At this instant,a bizarre thing occurred:My salt disappeared.