试题题干
WORD FORMATION
Complete the following sentence with the proper form of the word in the bracket.
(construction) The old professor made a number of very 
suggestions
concerning soil conservation in the area.
参考答案
试题解析
suggestions是名词，需要形容词修饰。变construction为constructive。
句意：关于土地保护方面，老教授给出了一些建设性的建议。