以下梅毒患者不具有传染性的是()
A.感染后1~2年内
B.感染4年后
C.潜伏期患者
D.妊娠妇女
参考答案:B
()的闪点>28°C。
A、松节油
B、甲醇
C、煤油
D、汽油
E、柴油
—Why, my new computer is rubbish! Five hours has passed and it still hasn’t finished the downloading.
—Don’t worry. You know, sometimes the Internet ________ be very slow.[ ]
A. can
B. may
C. should
D. must