"skydiving is a hazardous sport" "extremely risky going out in the tide and fog" "a wild financial scheme"
"a bad investment" "high risk investments" "anything that promises to pay too much can't help being risky" "speculative business enterprises"
牛津高阶第八版
美国韦氏词典
Dictionary.com
Free Dictionary
维基百科 (自由的百科全书)