This is a key to opening this door这句话有问题吗?This is a key to opening this door.还是This is a key to open this door.是哪个对?这里的to是当作介词还是不定式?

This is a key to my door.(翻译) This is a key改为一般疑问句? This is a key.(变为复数) this gate requires a key to This is a white key 的提问This is a white key ,对“a white key 进行提问 This is the key ____the classroom.A.to B of C at D in This is the key __the door.A of B with C to D in This is the key the ___ciassroom.A.to B.of C.at D.in This is a key to opening this door这句话有问题吗?This is a key to opening this door.还是This is a key to open this door.是哪个对?这里的to是当作介词还是不定式? is there a key to the door The teacher said this is the ______ to this question.A.way B.means C.key D.method what's this?A this is key B it's key应该选几 Please( )this key to your sister.She is at school 填A biing B brings C take D to take This is a key.（对划线部分提问）划线部分：a key._______ ________this? This is a key.a key画横线 对划线部分提问 This is a key in Engelish.(对划线部分提问)a key是划线句 连词成句英语is,in,a,English,key,this This is a key.(对划线部分提问）