If you already know about Quizlet live, you will like this one - Quizlet live can now be played as individual, which can be great for online classes.
This is a great option for the physical classrom but you could also play it online if you have the option of breakout rooms (i.e. in Zoom).
You can also create diagrams/ pictures with labels (e.g. house, foods, body etc). Browse the many sets that are ready to go.
This is a great collection of ideas for using Quizlet study sets offline and online. It's a great blend and can be continued when back in the classroom.
You can also combine several Quizlet sets to make a big set for end of semester/ year practice.
Try to use Kahoot Challenge online with your students.
There is no free version anymore. They have added Gimkit Ink, which looks like a great publishing tool for student work/ projects.
Source:
Graham, Stanley: Language Learning with Technology. Cambridge Handbooks for Language Teachers. Cambridge: University Press, 2013.