cost
(as i found) to my cost
意：吃了苦头才…(明白、知道);付出了代价才，一;身受其害后我才
例.I know it to my cost.
这一点我是吃了苦头后才知道的。
Diving can be a very dangerous business, as I found to my cost.
吃了苦头后我才知道，跳水有时是件很危险的事。
Wasps' stings are serious, as I know to my cast.
我知道被黄蜂童了是很严重的事，因我曾身受其害门.
