岁（suì ）：year
subject +几岁了: for children usually less than 10:
eg. A：他几岁了？
B：他两岁了
subject+多大了？：for adults
subject+多大岁数了：for old people
eg. A：你爷爷多大岁数了？
B：我爷爷（奶奶）84岁了。
Natural Chinese
chinese learn Culture China
subject +几岁了: for children usually less than 10:
eg. A：他几岁了？
B：他两岁了
subject+多大了？：for adults
subject+多大岁数了：for old people
eg. A：你爷爷多大岁数了？
B：我爷爷（奶奶）84岁了。