北大西洋冰况图上的三角形符号或表示()
A.海水结冰
B.陆源冰
C.A、B都对
D.A、B都错
参考答案:C
There ______ lots of bad information which is not ____ for teenagers on the Internet.
A.seem to be; suitable
B.seems to have; fit
C.seem to have; fit
D.seems to be; suitable
简述聚氯乙烯糊树脂的危险性?