bonjour merci de bien vouloir m'aider pour ce probleme Complète ces phrases avec for et since. 1. Electric cars have been greatly improved they were created. 2. Developed countries have conducted many green actions ...... the beginning of the 21st century. 3. Our school has adopted a greener policy a while now, and it has been very positive. 4.The global surface temperature has often varied ...... 1980. 5. Sea levels have risen constantly ...... the past 50 years.