| 复合形式： |
| trade in [sth] vi + prep | (sell) | 出售，销售，卖
|
| | This company trades in industrial machinery. |
| trade in vtrtransitive verb: Verb taking a direct object--for example, "Say something." "She found the cat." | literal (sell, deal in) (本义) | 买卖…，出售…，做…生意
|
| | He trades in stocks and bonds. |
| trade in vtrtransitive verb: Verb taking a direct object--for example, "Say something." "She found the cat." | (turn [sth] in as partial payment for new one) | （补差价）以旧换新
bǔ chā jià yǐ jiù huàn xīn |
| | | 以（旧商品）抵价换新商品
yǐ jiù shāng pǐn dǐ jià huàn xīn shāng pǐn |
| | I traded in my old car for a new one. |