It is clear that the whole world is passing through a social revolution in which a central _____ must be taken by scientists and technologists.
―Are you still able to speak French and Russian? ―I _________. But I can only remember few French words. No Russian words at all now.
She would love to have gone to the party, but she _______ extra hours to prepare for a meeting.
The two sides _______ to make peace, but something unusual _________.
It was said that other possibilities ________ at the meeting the day before yesterday.
―Kate doesn’t look very well. What’s wrong with her? ―She has a headache because she ________ too long; She ought to stop work.