ball and socket joint

基本解释

Ball and socket joint at shoulder allows movement in 3 planes.
球窝关节―在肩膊容许三平面的运动。
They made joints in stone keeping the lintels in place horizontally using a tongue and groove joint and subsequently fixing the upright and lintel with a ball and socket joint or mortice and tenon.
石匠们用楔口连接法将楣石水准放置，将石块连接起来，然后将这些直立的石块和楣石用球窝接头或楔口接头来固定。
They made joints in stone keeping the lintels in place horizontally using a tongue and groove joint and subsequently fixing the upright and lintel with a ball and socket joint or mortice and tenon .
石匠们用楔口连接法将楣石水平放置，将石块连接起来，然后将这些直立的石块和楣石用球窝接头或楔口接头来固定。