Finally came the day ——— he had to begin his study for the next term.Atill Bwhen Cwhich Dthat

题目

Finally came the day ——— he had to begin his study for the next term.Atill Bwhen Cwhich Dthat

答案

用 WHEN
前面是时间的,后面用when指代,
是人的,用who,或who.