1.The most effective “weapon” of       peacekeepers       (peacekeeper) is the support of the international community.

2.The construction of a dam influences downstream channel         stability       (stable) in two ways.

3.I was a new, idealistic teacher when Billy entered my         fourth       (four) grade.

4.It was not long before a helicopter arrived on scene to rescue the       survivors       (survive) of the plane crash.

5.Mr. Block hit the ceiling when he was asked         senseless      (sense) questions.

6.It was he who, so he would argue, had brought about the         destruction       (destroy) of Mr. Heath.

7.Do you forgive your thoughtless friend for her         cruelty       (cruel)?

8.It provided the         motivation       (motivate) for controlling smoke and dust emission from industrial plants.

9.We now travel round the world in a way       previously       (previous) undreamt of.

10.I felt angry with my little sister greatly, but her innocent smile      disarmed       (disarm) me.

11.You show promise as a musician but your lack of practice is keeping you       back       .

12.Far from moving back, he threw all his time and energy         into      his work.

13.Shops are being forced to put their prices       down       in order to attract customers.