把They are 50 yuan 这句话改为疑问句.急

把They are 50 yuan 这句话改为疑问句.急 They are three yuan a____________ this pair of shoes_____ 50 yuan they are cheap. ______are they?They are forty yuan. how much ( ) are they they ( )40yuan how much is that pair of trousres it's 50yuan 还是they are 50yuan are the shose?They are 25 yuan 英语的名词复数How much are these pants? They are 89 yuan. That's expensive. 第三句对不对,可以把that's 当做价格来说吗,还是必须要用They are expensive? They are a hundred yuan(对a hundred yuan提问) They are five yuan根据答句写问句 把They are apples.改为单数句 there are mnay hats.they are 10 yuan each（合并为一句）Many hats are___ ___ ___10yuan each. 翻译:Are they ok?They're three yuan. How much are the apples?【 】(it/They)are eight yuan 什么are these tomatoes?They are 2 yuan a kilo. The pants are really .they only cost me twenty yuan H m are these trousers?They’re 400 yuan. I want five apples.They are three yuan.I also want ten bananas,five pears and two watermelons.That's fifteen yuan.为什么上句主语用的是they,而下句则用that,这里的单复数怎样来判断?