51吃瓜

??? ???????? ???? ???? ??? ?? ??????? ??? ??? ??? ??. ?? ?? ??? ?? ???? ?????? ?? ???? ???:

1. ??? ?? ?? ????: ??? ?? ??? ?????? ??? ???? ??? ??? ???? ??? ?? ??? ???? ??????.

2. ????? ????? ??????? ????: ?? ?? ??? ????? ??????? ?? ???? ??? ???? ?? ??? ????? ????? ??????? ?????

3. ???? ?? ??? ????? ???? ?? ??? ???? ???? ??????? ???? ?? ???? ??? ???? ?? ????

4. Reasonable lubrication: Reasonable lubrication can effectively reduce friction and lower the risk of scratches.

5. ??????? ????? ?? ???? ???: ??????? ???? ????? ??? ?? ??? ?? ????? ?? ??? ????? ?? ???? ???.

?????? ?????? ?? ?????? ?? ??? ??????? ?????? ??? ??? ?? ???? ??? ???? ?? ??? ?? ???? ???.