The Marriage Law stipulates that it is one of the conditions for a separation of two years due to the incompatibility between husband and wife; The most fundamental condition is that the relationship between husband and wife is incompatible, and they really cannot live together.
 Common evidences that can prove the separation of husband and wife:
 1. The lease contract of the house where one party lives outside;
 2. The written agreement on the separation of husband and wife signed by both parties must be in writing, and the oral agreement must be acknowledged by the other party;
 3. The written separation document sent by one party to the other party should preferably be sent by express mail, with "separation" indicated in the remarks column, and the mailing certificate kept. The period from the date of mailing to the filing of divorce belongs to the separation time of husband and wife;
 4. Letters and emails from both parties can prove the fact that the two parties are separated from each other;
 5. Personal testimony can also be used, such as friends or relatives who both parties know. However, because witnesses often have interests with the party who testifies for them, and separation is a "private matter" of husband and wife, it is difficult for the court to accept the testimony of a single witness, and other evidence should be supplemented.