and they sleep through the six months that

and they sleep through the six months thatand they sleep through the six months that they need for digestion.
请问一下这句话中的that是什么意思？该如何翻译？前面是：并且他们需要经过六个月的休息。后面是：他们必须消化掉。that如何翻译？这句话连起来应该是什么意思？

and they sleep through the six months thatand they sleep through the six months that they need for digestion.
请问一下这句话中的that是什么意思？该如何翻译？前面是：并且他们需要经过六个月的休息。后面是：他们必须消化掉。that这样翻译，这句话连起来应该意思是需要睡6个月才能消化点，that只是连接词。

需要睡6个月才能消化点，that只是连接词 再看看别人怎么说的。