22.I had traced the cause of the trouble.
因?yàn)槲艺业搅嗣∷凇?/p>
23.One of the links in the chain that drives the wheels had snapped.
驅(qū)動(dòng)輪子的鏈條斷了一節(jié)。
24.After buying a new chain I was faced with the insurmountable task of putting theconfusing jigsaw puzzle together again.
我買來一根新鏈條后,面臨的就是如何把這些令人眼花繚亂的拼板重新組裝起來。