1. git pull 报错：refusing to merge unrelated histories
This question appears (not related to the merger refused history) reason is that the local repository and remote repository is actually two separate warehouses. If before I was directly clone a way to establish remote github repository in local clone a local repository would not have this problem.
Can be used immediately after the pull command --allow-unrelated-history option to solve the problem (this option can merge two historic warehouses independent start).
$ git pull origin master --allow-unrelated-histories
We have been successfully pull, after the settlement of the conflict can push.