Bonjour
1- Tous les jours je m'habillais en noir.
2- Hier, je suis allé au stade.
3- Il faisait froid au Canada en janvier.
4- Nous avons eu faim le soir après le ski.
5- Quand tu étais petit, le matin tu allais à l'école et après tu voyais un film.
6- Ils étudiaient le français l'année dernière.
7- Je mangeais quand tu as téléphoné.
8- Vous aviez cinq chiens en 2002.
9- Le premier jour, nous avons visité le Louvre.
10- Il était minuit quand ils sont rentrés.
I'd like to explain but as a French guy, I just can't !!!!!
all I can say for sur is for n°7 and 8 = i'ts exactly as your preterit be + -ing (progressive) + preterit simple.
1- every day = repeted, habitual actions
2- hier = yesterday = near past
3- en janvier = it is always cold in Canada, it's something usual so -- imparfait . (if the sentence had been = il -- en août = so it would have been = il a fait froid au Canada en août .. because it's unsual)
4- near past
5- when you were .. --> it's in the past and over
6- l'année dernière = last year = past ==> it's over
7- je mangeais quand tu as téléphoné = same as in English.. you were doing something, when it happened
8- en 2002 == again, it was a long time ago, it's over, no relation with today
9- le premier jour = it has a connection with the present..--> passé composé
10- ...quand ils sont rentrés = as in English; you use both tenses
did my best to try to explain, knowing that sometimes, we (when talking every day, we don't sometimes respect our grammar rules !!!!!) . But I tried to follow our french rules !!!!!