1. The validity period of a visa (“Enter Before”) refers to the valid time length of the visa itself. A visa is valid for the visa holder to enter the Chinese border from the date the visa is issued to the expiry date (as of Beijing Time). If a visa has unused entries, the holder can still use it before the expiry date (inclusive).
2. The term "Entries" of a visa refers to the number of times the visa holder is permitted to enter the Chinese border within the validity period of the visa. A visa becomes invalid if all the entries are used up or if the visa has expired even though there are entries unused.
In this case, you will have to submit a new visa application if you wish to visit China. Holders of an invalid visa will be refused entry to China at the border.
3. The "Duration of Each Stay" refers to the maximum number of days a visa holder is permitted to stay in China after each entry, namely, the maximum number of days a visa holder can stay in China from the day of entry.
Foreign citizens who stay in China longer than permitted by the visa without applying for an extension of stay will be considered as violating the Law of the People’s Republic of China on Control of the Entry and Exit of Aliens and Rules Governing the Implementation of the Law of the PRC on the Entry and Exit of Aliens, and as a result will face prosecution of fines or other penalties. Therefore, the visa holder must apply for an extension of stay at local public security authorities above county level (detailed requirements are available on the websites of local public security authorities) should it be foreseeable that an overstay would happen. (However, approval of the application cannot be guaranteed.) Chinese embassies and consulates in foreign countries do not accept applications for visa extension.
Holder of D visa, J1 visa, Q1 visa, S1 visa, X1 visa, Z visa must register with local public security authorities for residential formalities within 30 days of entry. Resident members of diplomatic and consular missions must complete residential formalities at the Ministry of Foreign Affairs or local foreign affairs departments within 30 days of entry.