According to French media reports, the order count for China's domestically produced large aircraft C919 has reached 1,061, with a total order value exceeding 700 billion, "likely to completely end the era of Boeing and Airbus dominance." Under the strong impact of C919, the performance of the American aviation "giant" Boeing has seen a rare negative growth, with over 4,000 aircraft facing a "cancellation wave," setting the highest loss record in 50 years. Currently, Boeing executives are seeking assistance from US Commerce Secretary Raymond to curb the development of China's commercial aviation project by cutting off the supply of C919 engines. So, what engines does C919 actually use? Is it true that China's domestically produced large aircraft are assembled using foreign parts? Is the tactic of cutting off aircraft engines effective in curbing China's commercial large aircraft development? Today, I will share my views with everyone. As we all know, despite the advanced technology of C919, there are still many doubts, one of which is the relatively low domestication rate of C919, at only 60%. Critical components like engines require imports, so it cannot be considered "fully domestic." How should we approach this issue? Is the domestication rate important? First, I'd like to share my perspective. Those who question the low domestication rate of C919 are generally non-experts. Commercial products are not military products; they prioritize product performance rather than domestication rate. For commercial products, what matters is selling well, and that's what defines real quality. Therefore, no aircraft manufacturer pursues this metric. Airbus and Boeing also have low domestication rates; Boeing 737 is only 50%, and Boeing 787 is just over 30%. As for Airbus, it's even more of an international brand.