Native speakers! Please take my pronunciation survey https://www.englishspeechservices.com… THANK YOU!
A discussion of why English speakers in various countries pronounce ‘sh’ at the start of words like ‘street’ and ‘strong’.
MRI videos from University of Glasgow:
Josh at English Hacks on ‘tr’ and ‘dr’:
Keenyn Rhodes on ‘storm chroopr’:
Hank Green (thumbnail) Creative Commons Attribution 3.0 Unported license