請問 英文 1.Hamburgers are my favorite food. 2.Mia and Jack's morther are housewives. 為什麼1的food 是 單數 2的housewives是複數?

(1) "Hamburgers are my favorite food."
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a) "Hamburgers" 指 cheese-burger, fish-burger, ... 等 不同款式的 hamburgers.
因此, 應寫 "不同款式的 hamburgers" ARE ...
b) 這句的含意是 : Among various TYPES of food (noodles,cakes, ...),
"hamburgers" 這一款 是我的 "favorite food". [ 一款 食物, ∴ 用 food (NOT foods) ]

(2)
a) "Mia and Jack's mother are housewives."
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≡ Mia's mother and Jack's mother are housewives.
有 2個 mothers, ∴ 用複數 "housewives" !

b) "Mia and Jack's mother is a housewife."
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≡ Mia 和 Jack 的媽媽 是個 housewife.
[ 即 Mia 和 Jack 是姊弟關係 ]

# 提示 :-
" . . . are housewives" → 兩人來自不同的媽媽
" . . . is a housewife" → 兩人來自同一個媽媽
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補充 :-
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"food" is uncountable in general use.
"food" can be countable when considering TYPES of food.

(1)food is uncountable,eg:-food and water, food stuff is singular in form but plural in meaning.Can be countable if attribute to types of food.
(2)"housewife" can be plural in no.if attribute to more than one.Hence "housewives".

food是食物是集合用法
簡單來說水果蔬菜速食等等都是屬於食物
所以食物為不可數

housewife家庭主婦可以有很多個
所以用複數