Students feel sad because they didn't pass the exam,they()ha

Students feel sad because they didn't pass the exam,they()ha l'm sad because l ___ the exam a.don't pass b didn't pass They didn’t pass the exam last time,I regretted _____. I didn’t know ________ they could pass the exam or not． 求住英语高手12.They didn’t pass the exam last time,I regretted ___ Some students （ ）fail in the test because they don’t work ha He didn't pass the exam because he didn't study hard.(对划线部分提 He didn't pass the exam because he didn't work( ). I don't believe they can pass the exam,_______? many students didn't pass the english exam.many students ___ They didn't pass the ball often enough,___ they didn't play she didn‘t pass the final exam