They've made friends since they came to China这句话哪里错了?

They've made friends since they came to China这句话哪里错了?
They've made friends since they came to China这句话哪里错了?

They've made friends since they came to China这句话哪里错了?
since 是一段时间,这么表述的话成了从他们到中国以来就一直在互相交朋友,不太正常,所以应该是They've been friends since they came to China.从他们到中国以来就一直是朋友

They has made some friends o.O
have sth since sth
这里somebody since 。。。貌似也不是很通畅o.o
They has made some friends when they came to China. 当他们来到中国的时候交了一些朋友。

应该是 They had made friends since they came to China.