Pronunciation Practice:
The voiceless "th"
English Learners from Vietnam might find these videos useful:
Video Series: HelloChao
How to say the initial “sh” sound, “t”; “st”; words like nature, teacher, question
http://www.hellochao.vn/phuong-phap-hoc-tieng-anh-hieu-qua/phat-am-d-giong-ban-xu-theo-cach-de-nhat-hellochaotv/?act=detail&m=video&iid=a87ff679a2f3e71d7181467b754212Mm&page=1
Youtube—IPA alphabet in Vietnamese (with Miss Lan)
-ed endings