Bonjour,

Réponse :

a. " Are you going to South Afriica this summer?"

" No, I'm not, unfortunately!"

b." Did you watch the documentary about wildlife in Africa last night ?"

" Yes, I did."

c." Do you think Mandela was a great man?"

" Yes, I definitely do."

d. " Have you read his autobiography Long Walk?"

" No, I haven't. Not yet"

e. " Has South Africa changed since Aparttheid ended?"

" Yes, it has."

f. " Does South Africa belong to the Commonwealth?"

" Yes, it does."

Explications :

a. présent Be+ BV-ing   ===> auxiliaire "are"

b. prétérit ===============> auxiliaire "did"

c./ f.  présent simple======> auxiliaire "do" /"does"

d./e présent perfect ======> auxiliaire "have" / "has"