There are a number of organizations and books that can help you learn more about

游客2025-02-04 41

问题 There are a number of organizations and books that can help you learn more about ______indoor air quality.

选项 A、to improve
B、how to improve
C、improve the
D、how improve

答案 B

解析 The infinitive phrase how to improve is the object of the preposition about.

转载请注明原文地址:http://tihaiku.com/zcyy/3942424.html

相关试题推荐

随机试题

最新回复(0)

1ThenumberofinsectspeciesonEarthexceedsthatofallotherlifeformscom