你好！我住在上海找中文朋友。　

我学中文因为工作的原因。我已经在上海两年了。十二月份考HSK五级。　

我有一个学生已经再考六级了，加油吧

你好！我住在上海找中文朋友。　

我学中文因为工作的原因。我已经在上海两年了。十二月份考HSK五级。

 I'll correct what I know:

'我住在上海找中文朋友"

*中文朋友 should be 中国朋友. 中文 refers to Chinese languages. 中国，refers to Chinese associated words, i.e. 中国人- Chinese people.

* i'm not sure what you mean. "I live in Shanghai, I'm looking for Chinese friends" ? I would write it as: 我住在上海，我在找中国朋友. 在 + verbs are the same as adding "ing" to the end of a word in English(the action is happening now.)

我已经在上海两年了 I would change this to 我已经在上海住了两年。(I already been living in Shanghai for 2 years) 

你好！我住在上海,想找找中文朋友。　

我学中文是因为工作的原因。我已经在上海两年了。十二月份考HSK五级。