下列做法会导致食品对人体健康有害的是[ ]
A.用干冰保藏易变质的熟食
B.用牛奶经工业发酵后得到酸奶
C.用工业用盐代替食盐炒菜
D.用聚乙烯薄膜包装食品
答案:C
Look out! Don't get too close to the house ______roof is under repair.[ ]
A. whose
B. which
C. of which
D. what
基础梁的代号为______。
A.JL
B.WL
C.QL
D.GL