In the past few years,traffic problems(become)___more and more serious.为什么用have become,

in the past few in the past few years in the past few years造句 in the past few centuries是什么意思 in the past few years 过去完成时 in the last few years 现在完成时 in the past 一般过去时 in the past year 什么中文意思 【英语】请问in the past few days与for the past few days有区别吗? There( ) great changes in Shanghai in the past few years. 英文报纸上的句子~Chirac's efforts in the past few year to spearhead efforts to lift the unreasonable European arms embargo on china. in the past few years 用什么时态? in the last / past few years的用法 shanghai _______ (change) a lot in the past few years in the last year时态问题这与in the past few years 有什么区别?是不是in the last year是没有the的?可以用现在完成也可以用过去完成而in the past few years只能用现在完成?不清楚的话 请不要乱说 高三了 英 in the past few years和in the last few years的区别, in the last few days 和 in the past few days 是否可以互相替换? what do you think__to protect our environment in the past few year?A to do B was done C has been done D have done In the past (a few;few)years,great changes have taken place in my gometown. in the last few decades和over the past few decades 意思一样吗?