安装在前部和后部的垫片厚度可能不同。

There is a possibility that the thickness of filler plates for front and rear mount is different.

youdao

在前部的，向前的位于或朝前的；向前。

Located at or toward the front; forward.

youdao

在前部分提出问题。

Ask the question up front.

youdao

Particularly the front of the eye, the cornea and the sheet that covers the cornea was particularly damaged.

尤其是眼睛前部，角膜和盖在角膜上面的那层薄片,严重受损。

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