I don't now how good I am at writing, but the truth is that I am better at writing than at speaking. When I have to write e.g. a letter or a story I have time to create these articles. I'm not nervous and if it is necessary I can correct my mistakes. I don't remember much about the rules how to write formal or informal letters, how to write a story or applications.

I am able to use some tenses (simple present, present progressive, simple past, past progressive, present perfect simple, present perfect progressive, past perfect simple, simple future), but on the other hand, I have some problems to use wit the others tenses (future perfect continuous, future perfect and sometimes also conditionals).

Writing is easier than speaking, because when I don't have any idea what tense I should use, I have time to find out a solution of the problem and create good sentences.