My personal favourite is your last one: - I can write English as good as he does. I would change it slightly though, I think this is better: - I can write IN English as WELL as he does. Because: You write In a language, you don't write a language. Also, something can be good but you can do something well. So changing good to well is suitable in this sentence. HtH - Rob.

i can write english like how he does. it is wrong

helpful..but someone please illustrate it more. I still dont get which ones are right and which are wrong.