As a rough guide, a horse needs 2.5 percent of its body weight in food every day.
作为一个大致的标准，一匹马每天需要相当于它体重2.5%的食物。
《柯林斯英汉双解大词典》
2
However, it should be considered as a rough guide because it may not correspond to the same body fat percentage in different individuals.
但是，它应当被视为一种粗略的指导，因为在不同的个人身上，它或许不能反映为同样的身体脂肪百分比。
3
They'd both looked down at the snake then, its eyes like two pebbles, its body all but indistinguishable from the length of rough wood it was stretched out on.