Why is Gu Ailing allowed to be a dual national?

Many overseas Chinese, including Gu Ailing, have acquired foreign nationality, but they have not settled in foreign countries or returned to China for development after acquiring foreign nationality. In this case, China nationality will not be lost.

Then, doesn't Article 3 of China Nationality Law clearly stipulate that China does not recognize dual nationality? Does this situation contradict the provisions of Article 3 of the Nationality Law?

No contradiction, because article 3 only says that dual nationality is not recognized, that is to say. China does not recognize foreign nationality acquired by citizens of China.

So you legally obtained foreign nationality, but you didn't officially declare that you have settled abroad. In the eyes of the China government, you are still a citizen of China and have no foreign nationality.

However, there are spatial differences in their identities. Children born in the United States become China citizens in China and American citizens in the United States after being registered in China. It is also based on Article 3 of China's Nationality Law: "People's Republic of China (PRC) does not recognize dual citizenship of China citizens".

The China government will not recognize the foreign nationality of China citizens unless I formally renounce my China nationality. However, according to the first two misunderstandings, China's nationality law has actually acquiesced in dual nationality.