问题
选择题
| Yuan Longping devoted himself to ____ hybrid rice. |
[ ] |
| A. research B. researched C. researching D. researches |
答案
答案：C
搜题请搜索小程序“爱下问搜题”
| Yuan Longping devoted himself to ____ hybrid rice. |
[ ] |
| A. research B. researched C. researching D. researches |
答案：C