Answer: With the continuous development of economy and the diversification of economic models, the theory of trademark confusion has also shown diversified development. Trademark confusion refers to the fact that the last trademark is the same as or similar to the previous trademark and used on the same or similar goods or services, so that consumers are confused and think that the goods used in the last trademark are provided by the prior trademark owner. In other words, trademarks are destroyed by this confusion through their function of distinguishing different operators. From the perspective of protecting the economic interests of trademark owners by trademark law, it is an important issue that legislators and law enforcers cannot avoid to avoid the above-mentioned destruction. Generally speaking, to prevent trademark confusion is to let consumers know the source of the selected goods or services correctly. Therefore, the premise of the normal realization of the trademark recognition function is that the provider of goods or services can be accurately instructed by the trademark. Only by protecting the trademark recognition function can the trademark owner invest more cost to maintain the quality of goods and services. Trademark identifiability, that is, whether there will be confusion between trademarks held by other operators and trademarks of trademark owners, is the focus of initial trademark theory. The economic value of a trademark is mainly reflected in its owner's reputation accumulated through business operation. The better the reputation of a trademark, the greater the economic benefits it brings, and the greater the commercial benefits that the trademark owner obtains through the trademark. This growing commercial interest urges its owner to ask the trademark legal system to give this trademark higher attention and stricter protection. With the emergence of new interests, the traditional trademark theory has been revised by the theoretical circle, and scholars have begun to reflect on the defects of the traditional confusion theory in the protection of well-known trademarks. Pre-sale confusion, after-sale confusion and Lenovo confusion have begun to be included in the category of confusion theory; In order to protect the interests of well-known trademark owners, some developed countries began to incorporate the expanded dilution theory into legislation and widely use it in judicial practice. Therefore, how to prevent the goodwill of the trademark owner from being damaged by the confusing behavior of the infringer has become the key to trademark protection.