Observation, reason and experiment make up ______ we call the scientific method.
A. which B. how
C. that D. what
The other day we ______ some visitors from Switzerland.
A. had B. have had
C. will have D. had had
I gratefully ______ financial support from several local businesses.
A. contradict B. recommend
C. distribute D. acknowledge
Some of the material presented may not be ______ to you or your circumstances.
A. parallel B. similar
C. relevant D. optional
It was the first occasion ______ they had both found it possible to reach an agreement.
A. why B. when
C. which D. how
The tiny fire in the stove gradually ______, and it was getting dark outside.
A. died down B. put down
C. set down D. keep down
