中文：

委买是指委托买入，即投资者通过证券公司等中介机构，向市场上的卖方发出买入指令，并委托其代理执行。在股票交易中，委买是一种常见的交易方式，投资者可以通过委买来买入自己想要的股票。

委买的好处在于，投资者可以随时随地发出买入指令，而不需要亲自到证券公司营业部进行交易。此外，委买也可以让投资者在市场行情上涨时及时买入，避免错失机会。

然而，委买也存在一些风险。首先，由于委买是通过中介机构进行的，投资者需要承担一定的中介费用。其次，由于市场行情的波动性，投资者可能会面临较大的风险。因此，在进行委买时，投资者需要谨慎考虑自己的投资策略和风险承受能力。

英文：

委买 refers to the buying of securities through brokerage firms or other intermediaries. Investors issue buy orders to the sellers on the market and entrust the intermediary to execute the transactions. In stock trading, buying through brokerage firms is a common trading method, and investors can buy the stocks they want through this method.

The benefits of buying through brokerage firms are that investors can issue buy orders anytime and anywhere, without the need to go to the brokerage firm's branch office to conduct transactions. Additionally, buying through brokerage firms allows investors to buy in a timely manner when the market is rising, avoiding missed opportunities.

However, there are also some risks associated with buying through brokerage firms. Firstly, investors need to bear certain intermediary fees because the transactions are conducted through intermediaries. Secondly, investors may face greater risks due to the volatility of the market. Therefore, when conducting buying through brokerage firms, investors need to carefully consider their investment strategies and risk tolerance.