噪声对人体的影响:噪声():长期接触80dB以上的噪声,听力就有可能受到损害,在大于85dB的噪声环境中工作;噪声对()
参考答案:对听力的影响;人的生理和心理的影响
离子反应、复分解反应、置换反应和氧化还原反应之间可用下列集合关系表示,其中正确的是[ ]
A.
B.
C.
D.
—Our city looks more beautiful!
—Yes. Lots of trees and grass _____ since last year. [ ]
A. have been planted
B. are planted
C. will be planted
D. were planted