【单选题】I didn't manage to do it _____ you had explained how.
【单选题】I didn't manage to work out the plan ______ the teacher had explained how.
【单选题】I didn't manage to do it ____ you have explained how .
【单选题】I didn't manage to work out the problem ______ the teacher had explained how.
【单选题】《药品生产许可证》有效期届满,需要继续生产药品的,药品生产企业应当在有效期届满前多少时间内,向原发证机关申请换发《药品生产许可证》