Some of them can email the results to the teacher. Sometimes a little difficult to install. The time students wait for results is sometimes irritatingly long. Some require using cookies. Writing Practice Web forms for the student to fill out.
Activities are interactive and game-like.
You must host your creations on their site with advertising on the pages. You need to register an email address which means you may begin to receive spam. Tutorials - Explanation of Grammar, etc. All handout passed out in class can be put online for students who were not able to attend class and for students who have lost their handouts. Old tests can be put online for students to study.