中文：

大单买大单卖是股票交易中的一种现象，指的是在某个时间段内，有大量买入或卖出的订单。这种现象通常表明市场主力资金在积极介入，对股票的走势有较大的影响。

大单买入通常出现在股票价格下跌或横盘整理的时候，这表明主力资金认为当前股票具有较大的上涨潜力，因此积极买入。这种大量买入的行为往往会带动市场情绪，吸引更多的投资者跟风买入，进而推高股价。

大单卖出则通常出现在股票价格上涨的高位区域，这表明主力资金认为当前股票已经到达高位，存在较大的下跌风险，因此选择卖出。这种大量卖出的行为也可能会引起市场恐慌，导致股价下跌。

大单买大单卖是一种较为极端的市场现象，需要投资者结合市场情况和技术指标进行分析和判断。如果大单买入后股价持续上涨，说明主力资金在积极拉升股价，可以继续持有；如果大单买入后股价不涨反跌，说明主力资金在制造假象，需要谨慎对待。

英文：

What is the meaning of "large buy orders and large sell orders" in stock trading?

Large buy orders and large sell orders are extreme market phenomena in stock trading, indicating that a large number of orders are placed for buying or selling during a certain time period. This usually indicates that major market players are actively intervening and have a significant impact on the stock's trend.

Large buy orders usually appear when the stock price is falling or consolidating. This indicates that major players believe that the current stock has considerable potential for a rise and actively buy in. This大量买入behavior often drives market sentiment, attracting more investors to follow suit and push up the stock price.

Large sell orders usually appear in the high price area when the stock price is rising. This indicates that major players believe that the current stock has reached a high point and there is a high risk of a fall, so they choose to sell. This大量卖出的behavior may cause market panic and lead to a decline in the stock price.

Large buy orders and large sell orders are extreme market phenomena that require investors to combine market conditions and technical indicators for analysis and judgment. If the stock price continues to rise after large buy orders, it means that major players are actively lifting the stock price and can continue holding; if the stock price falls instead of rising after large buy orders, it means that major players are creating false positives and need to be cautious.