Buy mǎi and Sell mài

These two words are distinguished only by tone at oral level, which is a major difficulty.

• 买 (mǎi) : 3rd tone (descending-up) = Buy.
• 卖 (mài) : 4th tone (even and descending) = Sell.

Mnemonic trick: The character for "sell" (卖) has an additional element above that of "buy" (买). One can say that one needs to "possess something more" to be able to sell it.

Combined example: 买卖 (mǎimài) means "commerce" or "business".