此时经常用延续性动词。 时间状语常用since加一个过去的时间点,或for加一段时间,或by加一个现在时间。 例:Great as Newton was, many of his ideas have been challenged today and are being modified by the work of scientists of our time. 虽然牛顿是个伟大的人...
可见答案是C) have been challenged。A) are to challenge和D) are challenging都是主动语态,不可能是答案。B) may be challenged虽然是被动语态,但意思与全句内容不合,所以不对。 C) 表示发生在过去,但对现在仍有影响的动作或情况。通常用点动词,如:arrive, begin, f...
免费送您一杯咖啡,请慢用。 25 My computer is acting up again. ►act up (疾病)发作;(机器)出毛病;(孩子)调皮捣蛋。 ▷My left knee acts up in damp weather. 天气一潮我左膝盖就发...
更多内容请点击：初中英语必考16种时态整理归纳,暑期提前掌握!