With the help of high technology, many new substances（物质） in the past years.
A. discovered
B. have discovered
C. had been discovered
D. have been discovered
With the help of high technology, many new substances（物质）in the past years.A. discoveredB.
答案:2 悬赏:0 手机版
解决时间 2021-12-18 00:12
- 提问者网友：邪性洒脱
- 2021-12-17 10:25
最佳答案
- 五星知识达人网友：你是病根
- 2021-12-17 11:18
A. discoveredB. have discoveredC. had been discovered(答案→)D. have been discovered解析：考查时态。根据句中时间状语in the past years在过去的多年，故用现在完成时态，选D。
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- 1楼网友：耳耳不睡觉
- 2021-12-17 12:17
你的回答很对
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