过去进行时的用法表示:He’spenfriend is an English boy.那一处错了？

He’spenfriend is an English boy.那一处错了？ By ____ he is an engineer. he is like an apple 对不对 I think he is an English. I think he is an English. Mr.White is _old.he is _old man.(an an,/ an,an /) He is an old friend of us. 这句话又没有问题？请解释原因？ He is working hard now with an eye ____ the future. he is _____ of an engineer. 用nobody 还是nothing? 为什么? HE HAD AN IDEA