Today, 111 years ago, on April 15, 1914 (March 20, 1914), China refused to accept the McMahon line. On April 15, 1914, McMahon made a partial amendment to the draft of the British treaty. On April 27, the British submitted an amendment and made a small concession. After the first signing of the British Tibetan representative, the British threatened the Chinese representative to sign, and claimed that if "not today, the second, fourth, two lines of the draft are deleted, that is, the contract with Tibet, and no longer consult with the nobles." Chinese representative Chen Huangpan was forced to sign the treaty, but then declared: "The painting and the signature, divided into two things, the signature in one layer, must be followed by a training order." On the 28th