Then read more English short articles and books with long sentences. The Bookworm series is good, so is Spark's, and so is Wang Changxi's Short Reading. I bought Wang Changxi's essays at that time.
Finally, you should listen to 1-2 hours of English listening every day to cultivate yourself to learn in an English environment. And practice speaking English often.
Good luck. Taking learning English as a pleasure won't make you bored. It's actually quite interesting.