they ____ (welcome) by their friends when they arrived there.

问题描述:

they ____ (welcome) by their friends when they arrived there.

were welcomed
首先,主从句的时态一致,根据从句的一般过去时,可以判断主句的时态也是一般过去时;
其次,be welcomed by sb 被某人欢迎,用的是被动语态
再次,因为是一般过去时,而主语是they,所以用were welcomed