11.   The university has planned a full day to observe the anniversary, beginning with a speech by Hunter-Gault.

12.   They argued that the anniversary should be observed quietly and solemnly.

13.   The trip was part of an effort to observe the anniversary of earthquakes that rocked the state a year ago.

14.   The president observed the anniversary two weeks early because he will be on a trip to Russia and Japan on the actual anniversary of the bombing.