 Activity for teaching modal auxiliary verbs, language tennis. A standard ESL classroom game that students young and old always seem to enjoy. It involves minimal preparation beyond planning the initial prompts. Either write your prompts on slips of paper or put them on the board. Organize students into two teams, and have them line up in two rows. The idea of the game is for you to crisscross up the line of students, getting them to say alternatives until such time as something is repeated, or a student can't think of anything new. At that point, the opposing team gets a point and you start with a new prompt at the person that was last to speak. Some suitable teaching points might be, can, ability, can, possibility, should, advice, must, obligation. Negatives can be used for any of these two. Language you would expect students to use for the prompt can, possibility, on a beach would be, you can sunbathe, you can play volleyball, you can see waves. If you manage to get up and down the line without any errors, simply end that round and move to the next prompt to keep up the fun variety element. These are some of the most interesting teaching tips for getting certified to teach English abroad and online.