sheep可數還是不可數用is還是are

　　The path was no better than a sheep track.

　　那條小路簡直就像是羊腸小道。

　　Stefano used a motorcycle to herd the sheep.

　　斯蒂芬諾騎一輛摩托車驅趕羊群。

　　Competitors have six minutes to shear four sheep.

　　參賽者們有6分鐘的時間來給4只羊剪毛。