二龙口衔盘沿,尾接瓶肩,呈双耳状立于瓶口两侧,它是唐代()。
A.白釉双龙尊
B.龙虎尊
参考答案:A
Laura __________ in the office for 4 hours. Tell her to have a rest, please.
A.works
B.was working
C.worked
D.has worked
正整数的补码与原码相同,负整数的补码与原码不同。