To improve my writing

I borrowed these books from KGU's library because I want to improve my writing skill. I think my writing is better than before. It is not so difficult to write some plane sentences in English now. But still, it is difficult for me to write smooth sentences. My sentences are often starts with same subject. I don't like that. It looks like the sentences a little child writes. So I borrowed these books and learned from them. One of them is the book for English discussion but I think I can use some phrase when I write logical papers. The other book called 'Eigo de kaku kihon ga minituku hon' is very useful. I learned many things I'd wanted to. I think it will help my writing very much. If you worry your writing skill, I recommend this book!