阿摩線上測驗
22. Fine particulate matter (PM2.5) is an air ________ that affects people's health such as causing or aggravating respiratory and heart disease.
(A) pollutant
(B) substance
(C) pollution
(D) objector
答案：登入後查看
統計： A(88), B(40), C(180), D(9), E(0) #2310659
統計： A(88), B(40), C(180), D(9), E(0) #2310659
