【C2】A．SinceB．ForC．AsD．In

My father has worked in this school ___ he graduated from college.A、sinceB、forC、after

【C7】A．SinceB．BeforeC．AsD．If

【C6】A．onB．forC．asD．in

You’ll have more chances of promotion ______ you work hard.A、sinceB、whileC、asD、once

【C2】A．sinceB．ifC．asD．while

【C6】A．uponB．forC．asD．to