Rubuta ci gaba don wannan sakin layi - Bayan kammala karatunsa a 1905, ya zama malamin harshen Faransanci da adabi a Giurgiu. A shekara ta 1907, ya koma makarantar sakandaren Traian a Turnu Severin, inda ya kasance har zuwa 1920, gami da zama shugaban makaranta. Daga cikin almajiransa akwai mai sukar adabi na gaba Şerban Cioculescu, wanda ya tuna da shi a matsayin mai horo. A lokacin hutun bazara, shi kaɗai ko tare da ɗalibai da malamai, zai yi tafiya zuwa gidajen tarihi na zane-zane a Austria, Jamus, Italiya da Faransa. Ya bayyana goyon bayansa ga tawayen Manoman Romania na 1907
, kuma a watan Janairun 1917, a lokacin Yaƙin Duniya na I, bayan ya la'anci hukumomin mamaye na Jamus, yana cikin masu ilimi da 'yan sanda sittin da aka kama a Turnu Severin. Bayan haka, an tura Oprescu zuwa Bulgaria, inda aka tsare shi a sansanin kafin a sake shi watanni da yawa daga baya. Daga baya, ya zama mataimakin farfesa a Jami'ar Cluj, wanda ke cikin yankin da ke ƙarƙashin ikon Romania tare da ƙungiyar Transylvania tare da Romania. A Cluj, ya ci gaba da koyar da harshen Faransanci da adabi, kuma ya kafa kuma ya jagoranci taron karawa juna sani na tarihin zane-zane. Yayin da yake halartar kwasa-kwasan kwararru a Faransa, ya zama babban aboki tare da Henri Focillon, wanda daga baya ya rubuta tarihin rayuwarsa, kuma an buga wasiƙunsa zuwa Oprescu bayan mutuwarsa.