to trade的用法和樣例：
例句
- Can I authorize my friend or-elative to trade?
我可以請親戚朋友代我操作券交易嗎？ - I refuse to deal with that firm any longer.
我拒絕不再同那家公司交易。 - His speculations in stocks led to his suicide.
他在股票上做投機買(mǎi)賣(mài)致使他自殺。 - The old trade in black ivory is on more.
昔日非洲黑奴的買(mǎi)賣(mài)已不復存。
