Bonjour,
Réponse :
a. Sonia has been babysitting for two years
.b. Kevin and Morgan have been looking after dogs since September.
c. I have been raking the leaves since 2019
d. Tom has been running errands for months.
e. Angie has been helping children with their homework for many years.
Explications :
Present perfect be + BV-ing :
sujet + have/has been + Base Verbale-ing ...
for ( depuis ) : durée
ex : x years ; x months; x days; a long time; many years ...
since ( depuis) : point de départ
ex : last year; last month; last summer; 2018 ....