【中文版】

大宗交易是指单笔交易规模远大于市场平均每笔交易规模，在交易所进行的特殊交易。这种交易通常由机构投资者或大型投资公司进行，因为它们拥有足够的资金和资源来进行大规模的交易。

大宗交易通常是在场外市场进行的，而不是在交易所的公开市场上。这是因为大宗交易的规模较大，如果直接在交易所进行交易，可能会对市场价格产生较大的影响。因此，机构投资者或大型投资公司会通过与交易对手方协商达成协议，在场外市场进行交易。

大宗交易通常涉及的证券种类包括股票、债券、基金、期货等。这些证券通常是大额的，因此需要机构投资者或大型投资公司来进行处理。在交易中，机构投资者或大型投资公司通常会采取一些特殊措施来保护自己的利益，例如分批购买、设置价格限制等。

总的来说，大宗交易是一种特殊的交易方式，适用于那些需要处理大量证券的大型投资者和机构。通过在场外市场进行交易，这些投资者可以保护自己的利益并避免对市场价格产生过大的影响。

【英文版】

Block trading refers to a special transaction with a much larger trading volume than the average market size, which is carried out in the exchange. This kind of transaction is usually conducted by institutional investors or large investment companies because they have sufficient funds and resources to carry out large-scale transactions.

Block trading is usually carried out off-exchange instead of in the open market of the exchange. This is because the trading volume of block trading is relatively large, and if it is directly traded on the exchange, it may have a significant impact on market prices. Therefore, institutional investors or large investment companies will negotiate agreements with counter parties to carry out transactions off-exchange.

Block trading usually involves securities such as stocks, bonds, funds, futures, etc. These securities are usually large-sized, so institutional investors or large investment companies need to handle them. In the transaction, institutional investors or large investment companies usually take some special measures to protect their interests, such as batch purchases, price limits, etc.

In general, block trading is a special trading method applicable to large investors and institutions that need to handle large volumes of securities. By trading off-exchange, these investors can protect their interests and avoid having a significant impact on market prices.