齿轮机构中，对于精度不高及圆周速度不大的大型齿轮，如果损坏一个或几个相邻齿，可以用镶齿法进行修复。 ()
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What does Matthew Kahn think of the new findings？
A. He thinks highly of them.
B. He is confused by the mixed messages.
C. He can easily understand them.
D. He doubts their validity.
高速机械高速转子用螺钉连接时，应注意附加防松装置对其平衡的影响。 ()
京剧的中国最大的戏曲剧种，已有300年的历史。()
The pursuit of instant results causes people to______.
A. have more errors in their writings
B. become more impolite
C. use voice messages instead of emails
D. lose many of their abilities in life
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