Confusing Words: "for," "since," and "ago"

I often hear or read francophones confusing the words "for," "since," and "ago." The following resources should help you demystify these words.

Website	Page Name	Comments
YouTube (هشام كرسيت)	For, since, and ago	"Quand utiliser for, since ou ago? Vous allez voire sur la vidéo qu'avec un peu de pratique, vous saurez quand utlisez quoi."  If you like the format of this person's videos, there are more videos on other grammar subjects here.
Learn English Today	For - Since - Ago	This website breaks down when each of these words is used, with examples.
Cambridge University Press	For, since, and ago	This is a .PDF document that presents the topic in more of a textbook format.
YouTube (melinda-gleeson)	For, Since, & Ago	This YouTube video also uses graphs as visuals to demonstrate where these confusing words take place in, temporally.
ESL Exercises	Quiz:  since, for, last, ago	Practice and confirm what you've learned with this quiz.
English Test	Words with time:  for, ago, since, on, at	Practice and confirm what you've learned with this quiz.