Looking for on-line English/grammar lessons

I have a friend who needs to improve his writing. Anyone know of an interactive English course?

Thanks

Purdue Owl

https://owl.english.purdue.edu/owl/

There are others if you google.

Also, go to a bookstore and get a basic "dummies" type book. It's good to have more than one resource.

Owl is a good self-directed instruction source. I have used it as an on-line reference source/text book. I wasn't aware that it also offered an interactive course.

Quite a few colleges are now offering on-line courses in a variety of subjects. Try looking in your favorite search engine to see which if any might meet your friend's needs. Note, an increasing number of these courses are now being offered free of charge.