.
It ________ I arrived at the station ________ I found the train was delayed.
| A．was until; that | B．wasn’t until; that | C．was until; when | D．wasn’t until; when |
Most experts agree that human activities such as the clearing of large areas of forests, and farming on a large scale _________ the problem of global warming.
| A．is leading to | B．is resulting in | C．are contributing to | D．are owing to |
With the help of the collected money, subways can be built sooner and better, _______ brings convenience to citizens.
| A．as | B．what | C．who | D．which |
We spent hours driving and another few hours waiting, only _________ that the plane would be delayed until midnight.
| A．to be told | B．having told | C．to have been told | D．told |
In the experiment we kept _____ watchful eye on ______ developments and recorded every detail.
| A．a; / | B．/; the | C．a; the | D．/;/ |
I remember the time _____ Eric won that speech competition.
A where B why C when D which