Up to now,our society __ with limited living space and a shortage of natural resources.A.has been challenged B.is being challenged为什么选A不选B

UP to now up to now 造句 up to now 造句 在线等英语对话：give advice to your friend on how to fight against sex discrimination in our societ英语对话.不用太多. just now ,so far ,up to now now it's up to up to now什么意思? Up to now的用法 用 up to now 造句 up till now 与up to now区别 up to now和up till now有什么区别 up till now和up to now的区别jiji up to now 和 up till now 的区别up to now和up till now的区别. Not only their knowledge will be well enriched,but also can they make contribution to our societ...Not only their knowledge will be well enriched,but also can they make contribution to our society.请问这句话有语法错误吗 up till now/up until now/up to now这三个用法有什么区别求解 Up till now有这种说法吗?Up till now是不是等于Up to now? 什么to our store now首字母c It'S Up To You Now 歌词