There are two stock exchanges in China, the Shanghai Stock Exchange and the Shenzhen Stock Exchange. The ups and downs of all companies listed on the Shanghai Stock Exchange will be represented by a composite index, which is the SSE Index. Similarly, there are deep evidence into fingers. The stock market referred to by shareholders mainly refers to these two comprehensive indexes, because it covers the comprehensive ups and downs of all listed companies in China and is widely representative, especially the Shanghai Composite Index. In addition, there are Shanghai and Shenzhen 300 Index, Small and Medium Board Index and Growth Enterprise Market Index. Among them, the Shanghai and Shenzhen 300 Index (the most representative 300 high-quality listed companies in various industries in Shanghai and Shenzhen stock markets) is the basic index of stock index futures.

To observe the opening double line, we must first observe the direction of the two K lines. If the two K lines are in the same direction, it means that there may be bulls (both positive lines) or empty sides (both negative lines) all day. Secondly, compare the physical lengths of two K-lines. If the entity of the second K-line is longer than the entity of the first K-line, it is a further confirmation of multi-party or empty energy. If the entity of the second K-line is obviously shorter than the entity of the first K-line, it means that the advantage of multi-party or empty side in the session is weak.

If the opening direction of the double line is different (one yin and one yang or one yang and one yin), compare the lengths of two K-line entities at this time. If the entity of the second K-line is obviously longer than the entity of the first K-line, then the direction of the second K-line indicates how empty the whole day is. The greater the contrast, the more obvious the power of many parties or empty parties. For example, the first K-line receives short Yin and the second K-line entity receives long Yang, which is a signal of multi-party counterattack. If the entity of the second K-line is shorter than the entity of the first K-line, it is of little significance to judge the trend of the whole day, because the whole day may be a shock equilibrium city.

Whether it is the opening double line or the opening three line, its significance is relative to the length of judgment. Their analysis conclusion is based on a kind of statistics, that is to say, judging the market trend of the whole day through the opening double line or the opening three line, the conclusion is often the same, but it is not necessarily the case, so we should pay special attention to it in the case of complicated news changes.