多大英語怎麼寫

有以下幾種情況：

1.幾歲用數字+year old

例如：給三歲的孩子買這麼貴的鞋真是太蠢了。

It's stupid to buy expensive shoes for a 3 year old.

2.問年齡：用age

例如：what's your age?

3.表達年的意思用year

例如：你多大了？比你大一歲.

How old are you? A year older than you.