Scientists say it may be five years _____ it is possible to
| Scientists say it may be five years _____ it is possible to test this medicine on human patients. |
| [ ] |
| A. since B. until C. before D. when |
可能相似的问题
你能帮帮他们吗
| Scientists say it may be five years _____ it is possible to test this medicine on human patients. |
| [ ] |
| A. since B. until C. before D. when |
你能帮帮他们吗