before they left home,they got their mother ___ them some sandwichesA packed B to pack C pack D to packing

they left the house an hour______(ago before) but they must wait before the green light is s_____ if they want to turn left. The two brothers have never been back < >they left their hometown.A.sinceB.forC.whenD.before They （）（study）the map of the country before they left for their holiday 动词填空. the students---------,---------they did not stop climbing 怎样做Chen Yu_______,__________he could not catch the bus before it left. t's a matter of time before they will discover John has left.此句(出自人教版高一下)是否有误? It is a matter of time they discover that John has left.该用before还是when为什么该用before和when哪个连词为什么 根据汉语提示完成句子：They---（study）the map of the country before they left.我认为可能是had studied或studied, before they left home,they got their mother ___ them some sandwichesA packed B to pack C pack D to packing before they are How come you didn’t tell me about this before?和How come they left you alone here!怎么理解这两个句 They told me that he left for the country some days 中空格应填A:soon B:before C:after D :ago They have___ left here.(刚刚) They left w__ saying goodboy. They left ______a rainy morning. The class went on with the story（ ） they had left it before the holiday.这个中间应该填什么 如果用WHICH的话 left 后面为什么加it? 高一英语课本中的句子“It is a matter of time before they will discover thatIt is a matter of time________they will discover that John has left.A.before B.when这两个答案该用哪个 The day before he left home.before he left home做什么成分