Subtitles are available on most video steps. You can turn subtitles on or off by clicking the speech bubble in the video player bar and then selecting the option you want.
[Image descriptor: The above image shows a course video player. The video still is a statue on a high tower overlooking a large body of water surrounded by trees. A large red arrow is superimposed over the video pointing to right to the captions button which has the options 'captions off' and 'English'. Next to the captions button are buttons for HD rendering and an expansion arrow button.]
If you click 'View transcript' under the video you'll find an inline transcript you can use to follow along if that's easier.
[Image descriptor: The above image is taken from the same video but now with an arrow underneath the video pointing to the left to the 'View transcript' button on the left underneath the video in pink. To the right of that button are the download video options of standard or HD downloads, again in pink.]
Most audio steps should have a downloadable transcript in the Downloads section at the bottom of the page.
[Image descriptor: The above image shows the downloads section at the bottom of the course page. There are buttons to go back and forth between the course pages labelled 'back to week 1' and 'introductions'. Beneath that is the title 'downloads' with a PDF link below labelled 'English transcript'.]