如果要of的話,那就要寫成：Food ran out.
run out of 是及物動(dòng)詞,后面要跟名詞.例如：We run out of food.
the sweater就是buy的賓語(yǔ),提前了.加it 就重復(fù)了.
祝你學(xué)習(xí)進(jìn)步!
望采納,謝謝!那為什么The sweater is so expensive that I can't afford to buy it.這里要加IT呵呵，這是因?yàn)檫@個(gè)事有一個(gè)狀語(yǔ)從句啊，從句也好，主句也罷，一定要有主語(yǔ)、謂語(yǔ)、賓語(yǔ)。而前面的那句話只有一個(gè)句子??！明白了吧，同學(xué)？再如：The shoes are too small to wear.The shoes are so small that I can't wear them.祝你好運(yùn)！