To me it makes sense to develop writing skill making comments online.
Start with by finding a site that encourages one-word comments. A photography site such as Flickr.com would do the trick. You can read what other people have written. Then repeat those comments—if you feel they apply—to other photos. Cut and paste if you need to (if the script is hard to wangle on your keyboard).
Gradually you’ll read, understand and be able to assign longer phrases and sentences.