为什么这句不用benzine而用petrol?——u should use [retrol] to get those stains off

为什么这句不用benzine而用petrol?——u should use [retrol] to get those stains off Where are my pens?请问这句为什么不用IS而用are? His hair needed cutting这句为什么用needed而不用need?这是张道真语法书上的一个例子 Greet changes have taken place the last three years.这句为什么用take place而不用happen there is no royal road to learning.请问这句为什么用介词加动名词而不用动词不定式呢 If someone said something bad about you,what would you do?这句为什么用something 而不用anything? Most people speak English as a second language.句中为什么用a,而不用the. everybody wants to be 句中为什么用healthy而不用health啊? everybody wants to be healthy什么意思句中为什么用healthy而不用health啊? He must not eat rich food 句中为什么用must而不用can he did not understand English.句中的为什么用did 而不用was? My nationality is American//Chinese.句中为什么用American//Chinese,而不用America//China? I don't think him a man to rely on ,for he is always lying.这句不懂为什么用him而不用herely on 为什么不用被动这句句式不懂 you have to give up smoking .改为否定句 为什么不用haveyou have to give up smoking .改为否定句 为什么不用have not 而用 do not 制造飞机不用钢铁而用铝合金,这是为什么 车轮为什么不用铁来做而用橡胶? 车轮为什么不用铁来做而用橡胶? 啤酒为什么用玻璃瓶而不用塑料瓶