green onion可数不我们老师怎么讲的不可数 onion是可数的啊 加个green就不可数了?

若当作一种植物看待,为可数名词,指“一根洋葱”“一个洋葱头”等.如：
The onions are beginning to sprout up. 洋葱正在抽芽.
There were stings of onions hanging on the wall. 墙上挂着一串一串的洋葱.
若指作为菜吃的“洋葱”“洋葱头”,有时可数,有时不可数.如：
(1) 可数用法：
Chop an onion finely. 把洋葱切细.
Onions have a strong odor. 洋葱气味刺鼻.
I like liver and onions for dinner. 晚餐我喜欢吃肝和洋葱.
Shall I use oil or butter for frying the onions? 我用普通油还是黄油来炒洋葱呢?
(2) 不可数用法：
The soup tastes of onion. 这汤有洋葱味.
There is too much onion in the salad. 色拉里的洋葱太多.
You’ve put too much onion in the salad. 你的色拉中洋葱太放多了.