difficult to fly还是difficulty to fly.fly不是动词么 副词修饰,为什么答案是形容词

difficult to fly还是difficulty to fly.fly不是动词么 副词修饰,为什么答案是形容词 是be difficult to sb 还是be difficult for sb? we thought ___ difficult for us to fly to the moon many years ago.ji I saw a bird fly to the north fly ing 是还是 fly is difficult to do sth .还是to doingis difficult to do sth .还是to doing sth, difficult后接to还是for to fly 英语翻译赏分外 再加分20聊表心意!golden skylet us fly-ay-ay-ay la-di-da-di-da-di-dahto the golden skyit's the paradise of smilewhere the sun will always shinela-da-di-da-di-da-di-dahwelcome to the wonderland,a place for you and meif you 他想放飞风筝 飞是用flying还是fly? 为什么?fly,to fly,flies,flying分别该怎么用? Difficult to it is difficult to do sth对还是it difficult to do sth对 it is difficult to do /doingit is difficult 后接to do 还是doing The problem was too difficult to be solved还是The problem was too difficult to solve? 我想飞 的英文说法?是 I WANT FLY 还是 I WANT TO FLY It's a good time _____kites in the park.是fly,还是to fly 是it is difficult to me to do sth还是it is difficult to me for sth还是it is difficult to me to sth 拂ti还是di much difficult 还是more difficult