注：平时练习时，可不用球，目视瞄准线自转是否成90度即可。

Side Note: No ball is needed during practice; just make sure the alignment device is always 90 degrees while putting.

youdao

注：平时练习时，可不用球，目视瞄准线自转是否成90度即可。

Side Note: No ball is needed during practice; just make sure the alignment device is always 90 degrees while putting.

youdao