例句與造句

1. Turn the vertical driving cam to the position where throat plate surface 3 and needle tip 4 align with each other , and the first or the second tooth of the top end of feed dog 5 descends from the throat plate surface
   讓針尖4與針板上面3對齊，在送布牙5的前端1 2齒從針板上面下沉的位置，轉(zhuǎn)動上下傳送凸輪，進行固定。
2. It's difficult to find second teeth in a sentence. 用second teeth造句挺難的