Leur, because it is singular
Bonjour,
Professeur Morel : Nous avons les examens cette semaine.
Professeur Bourdin : Les étudiants doivent étudier.
C. doivent
Have a good day ! :-)
Question 4.
Il est timide.
Question 5.
Ils sont sévères.
("Ils sont snobs" is also grammatically correct, but describing your parents as strict instead of snobby seems to be more appropriate)
Bonjour !!
To someone you don't know very well, you must use the "vous de politesse" which is a "formal you"
Comment <u>allez-vous</u> ?
<em>OR</em>
Vous allez bien ?
-
<em>if it was to someone you know well, as a friend, you'd say </em>
<em>Comment vas-tu ?</em>
<em>OR</em>
<em>Tu vas bien ?</em>
Hope this helps ☺☺☺