This is ________ difficult problem that few students can
| This is ________ difficult problem that few students can work it out. |
| [ ] |
| A. so B. so a C. such D. such a |
可能相似的问题
你能帮帮他们吗
| This is ________ difficult problem that few students can work it out. |
| [ ] |
| A. so B. so a C. such D. such a |
你能帮帮他们吗