那可能发生的，但属于非正常的变化，但是可能主链的化学变化将核苷酸结合在一起。
That can happen but that's abnormal, but changes in maybe the chemistry of the backbone that holds the nucleotides together.
虽然这两种技能很难结合在一起，也很容易受伤，但杨柳没有放弃。
Although it was difficult to mix the two skills together and it was much easier to get hurt, Yang Liu didn't give up.
它们虽各自独立，但结合在一起又衍生出新的东西；同时书与书彼此呼应，城与城相互牵连。
Although they are separate, together they all add up to something; they are connected with each other and with other cities.
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