我有歼击机
答案：It takes a long time to improve．这里是说客观事实用一般现在时，表示做某事花时间，用it takes sb+时间+to do sth，很长时间a long time，提高用及物动词improve，故答案是It takes a long time to improve．
融发装修
I have a good ability of English writing.orI have a good ability in writing in English.
