@Jiehfeng,
Write your tutorials how you want to write your tutorials. Everyone has different learning and teaching styles. As long as it delivers it's intended purpose, how you deliver it is up to you. You can take advice on what might work or how to better deliver your content but ultimately...
I normally don't post but I feel I have to give my two cents on this regarding responses, put simply:
If it's something you wont say to a stranger face to face, then don't say it online.
You guys are all awesome, be nice to each other.