R français

Beginning	un rat, riche, robe, Rome, rose, rue -- anglophone near-native speaker royal, royale -- from Ottawa, Canada raisin, raison, réel réelle, réussir à, récemment, responsabilité  -- from Limoges, France
After a consonant	bruit, croissant, froid, grand, je prends, trois électrique, sportif, sportive, prendre le métro, très stressé, très stressée
In the middle	différence, curieuse, curieux, sérieuse, sérieux Orangina, nerveux, nerveuse, irrité, irritée, direction, mer des Caraïbes
End The sound is a rush of air; not like the 'r' in the other places.	finir, dormir, partir, sortir, noir, noire, hier, cher, chère, art finir, dormir, partir, sortir, noir, noire, hier, cher, chère -- from Niger, Africa toujours, pour, bonjour -- from Haïti
Exception      Infinitives ending in -er have a sound like 'é' in 'école'.	aller, arriver, chercher, parler, porter, regarder entrer, rentrer, se coucher, employer, dépenser, acheter

Compare your pronunciation using a voice recording application. The French 'r' is sounded by vibrating the tongue against the back of the throat.  In the study of phonetics this is called a 'uvular r' (sign = R) because the vibrations occur at the place of the uvula, or glottis, of the throat.   See a diagram. The French did not always use the uvular 'r'.  History of R.