俄国第一个马克思主义团体-----劳动解放社是普列汉诺夫1883年在（）创建的。
A.华沙
B.基辅
C.彼得格勒
D.日内瓦
参考答案：D
Last Sunday, they arrived at the farm _____ they had never paid a visit before.
A．that
B．which
C．to which
D．for which
铜气焊时，选和什么牌号的焊丝？采用什么性质的火焰？
