什么是through sign language?急!

什么是through sign language?急! 什么是 vCenter Single Sign On 什么是 vCenter Single Sign On sign sign sign sign sign only if the first sign of life what sorrow winds through the paint 是什么意 为什么是across desert,through valleys,through mountains? auld lang auld lang Auld lang auld lang so.lang Sign through doors tell you where to go in or out.这里的through是什么意思?我认为它只有穿过通过的意思啊 through through