这要分情况讨论：
（1）、当用于表示蔬菜的种类时,为可数名词.e.g.There are two vegetables in my vegetable garden；
（2）、当用于表示蔬菜这一整体概念时,则为不可数名词.e.g.We should often eat vegetable which is good for us.
爷爷:grandfather /grandpa 这要分情况讨论：
（1）、当用于表示蔬菜的种类时,为可数名词.e.g.There are two vegetables in my vegetable garden；
（2）、当用于表示蔬菜这一整体概念时,则为不可数名词.e.g.We should often eat vegetable which is good for us.
爷爷:grandfather /grandpa