1. From the perspective of URL, the secondary domain name is more trustworthy than the secondary directory in essence. However, from the perspective of search engine ranking, it is recommended to use subdirectories instead of secondary domain names as much as possible.

2.二級域名和一級域名是兩個完全不同的網站，相當于兩個要推廣的網站。所有網絡營銷工作都必須再次進行。網站的公關價值和信任度將被這兩者分開。該站點是分散的。使用二級域名將增加網站的數量，但同時會使網站變小。子目錄將使網站變得越來越大。搜索引擎優化的非常重要的一點是網站的內容以及網站本身的質量和實力。網站的大小是重要的指標之一。

2. The secondary domain name and the primary domain name are two completely different websites, equivalent to two websites to be promoted. All network marketing work must be carried out again. The public relations value and trust of the website will be separated by the two. The site is decentralized. Using secondary domain names will increase the number of websites, but it will also make the website smaller. Subdirectories will make the website bigger and bigger. A very important point of search engine optimization is the content of the website and the quality and strength of the website itself. The size of the website is one of the most important indicators.

3.對于搜索引擎，第二級域名屬于一個獨立的網站，而子目錄實際上屬于主網站下的一個頁面。 二級域名和子目錄的權重較高。從理論上講，二級域名和子目錄在搜索引擎上的權重不高不低，但是對于不同的情況它們是不同的。對于新創建的子目錄和二級域名，子目錄更為重要，因為它們將繼承主網站的權重。對于搜索引擎，它與網站上的其他頁面沒有什么不同，并且將很容易被包含；

3. For search engines, the secondary domain name belongs to an independent website, while the subdirectory actually belongs to a page under the main website. Secondary domain names and subdirectories have higher weights. Theoretically, the weight of secondary domain names and subdirectories in search engines is not high or low, but they are different for different situations. For newly created subdirectories and secondary domain names, subdirectories are more important because they will inherit the weight of the main website. For the search engine, it is no different from other pages on the website and will be easily included;

二級域名起初非常重要，因為二級域名相當于一個新網站，除非主域名很高，所以二級域名基本上類似于一個新網站。如果它想被搜索引擎包括在內。換句話說，子目錄起初會比二級域名更好，但它們可能會朝相反的方向發展。

The secondary domain name is very important at first, because the secondary domain name is equivalent to a new website. Unless the primary domain name is very high, the secondary domain name is basically similar to a new website. If it wants to be included by search engines. In other words, subdirectories will initially be better than secondary domain names, but they may develop in the opposite direction.