Here is the recording you worked on today! Listen to it again and check your answers.
If it's a bit hard or if you want to watch the video corresponding to the recording to revise, here is the video (click on cc to get the subtitles):
If you want to watch another video on the matter, here is an interesting one! You can click on cc if you need to see the subtitles!
Here's yet another one!
Here is also a great article in which you will find interesting facts on the matter and a great infographic.
Here is an easier one:
