16. ---The farmer president was caught at last.
---Really? Where himself?
| A．had hidden | B．has he hidden | C．was he hidden | D．has he been hiding |
There is something wrong with my washing machine and it requires _____.
| A．repairing | B．to repair | C．being repaired | D．having repaired |
We walked a long way to see him off, only _____ that he had just left.
| A．found | B．to find | C．finding | D．having found |
The pen my brother gave me as a birthday gift _____ smoothly. I do like it.
| A．wrote | B．is writing | C．is written | D．writes |
I want to be a volunteer some day. I feel _____ is my duty to help others.
| A．this | B．that | C．them | D．it |
Mother kept me _____ during the summer holiday, for I failed my maths exam.
| A．study | B．studying | C．to study | D．studied |