________ the course very difficult，she decided to move to a lower level.(2013·北京，24)
A．Find B．Finding
C．To find D．Found
Volunteering gives you a chance ________ lives，including your own.(2013·北京，21)
A．change B．changing
C．changed D．to change
I got to the office earlier that day，________the 7∶30 train from Paddington.
(2013·大纲全国，25)
A．caught B．to have caught
C．to catch D．having caught
The witnesses ________ by the police just now gave very different descriptions of the fight. (2013·陕西，14)
A．questioned B．being questioned
C．to be questioned D．having questioned
Let those in need ________ that we will go all out to help them.(2013·陕西，13)
A．to understand B．understand
C．understanding D．understood
The airport ________ next year will help promote tourism in this area.(2013·四川，10)
A．being completed B．to be completed
C．completed D．having been completed
