This activity practices the passive form of the verb "use."
I start by teaching the students a fun English word that isn't often covered in class. Something like:
I tell the students that there are lots of people around the world who are studying Japanese right now. What kind of fun or useful words do you want to teach them? You might have to review the phrase "It means _____." A lot of students at the junior high school age might not have much of an idea that there are people in the world who don't speak Japanese, so you could help them out by showing them materials like a textbook for Japanese learners or a video of a Japanese class.
Once all of the students have thought of the word or phrase they want to teach, I ask them to ask each other what words they thought of.
I made this activity for classes in Japan, but with some small changes you could adapt it to classes in other countries as well.