作答如下,请详阅：
Experts 【are called】 in from many parts of the world to construct the domes and to decorate the walls .
来自世界各地的专家们被召集起来修筑这个圆形穹顶和装饰它的外墙.
ps：应该是说意大利的建筑吧.in from many parts of the world什么意思in是和call连用，【call in】召集，【are called in】被召集【from many parts of the world】来自世界上很多地方------[即]来自世界各地希望帮助到你！