将题后的单词转换为适当的词性，填入空格内.
1 Experience in a related field is a (   ) for this job.                require

2 He gave much (   ) to the problem but still had no answer.                reflect

3 This telescope is used for the (   ) of distant stars.                observe

4 You can work in here without any (   ).                disturb

5 The fire caused the (   ) of two buildings.                destroy

答案：
1 requirement

2 reflection

3 observation

4 disturbance

5 destruction