The connecting sentences between doubt and knowledge are as follows:

1. Look around in silence, and the woodcutter leaves no trace.

2. The broken begonia branches are shaken to reveal the moon, and traces of fragrance are scattered through the windows.

3. In my life, I had the knowledge of sorrow and demon, so I wrote about my leisurely and quiet life.

4. Yisu was three hundred years away from Han, and Yuanyou's affairs were similar to those of Yuanhe.

5. My sister is actually Jia Peilan, who is disabled for the first time in singing and dancing.

6. When the water in Kunchi merges with Lu, the grass in the imperial garden should be green? Speak slowly from the beginning to teach people's eyes to see temporarily.

7. Qi Xianying is the same as me.

8. The sound of the clouds stopped, and Zhang Juntian was happy.

9. Doubt is not only a necessary step for identifying falsehoods and eliminating falsehoods on the negative side, but also a basic condition for building new doctrines and obtaining new inventions on the positive side. The spirit of doubt is also a basic condition.

Contents related to doubt and learning:

1. Introduction to the author

Gu Jiegang (1893-1980), whose original name was Song Kun and whose courtesy name was Mingjian. A native of Suzhou, Jiangsu. Graduated from the Philosophy Department of Peking University in 1920. He is a famous historian, folklorist, founder of the "Ancient History" school in modern China, and a pioneer and founder of modern historical geography and folklore. He is the author of "A Brief Academic History of the Han Dynasty" and "The Preliminary Collection of Miscellaneous Knowledge of Shilin".

2. Appreciation of the article

At the beginning of the article, the article puts forward the point of view of this article with the help of the famous sayings of Cheng Yi and Zhang Zai: Scholarship must have a skeptical spirit. Then it explains the reasons for proposing this argument, and then explains in detail how to read and study with a "spirit of doubt", and summarizes the sub-argument that "skepticism is a necessary step in identifying falsehoods and eliminating falsehoods in negative aspects."

And in the last paragraph, another sub-argument is put forward: "Doubt is also the basic condition for actively building new doctrines and inspiring new inventions."