main roof slice的用法和样例：
例句
- That means that in the pressurizer there is a clearly horizontal interface between the main and jet flows.
即在稳压器受限射流时无论是正波动还是负波动，射流流体与稳压器内原有流体之间存在着明显的分层界面。 - A closer view of a thromboembolus filling a main pulmonary artery reveals a layered appearance, typical of a thrombus that formed in a large vein of the pelvis or lower extremity.
肺动脉主干内的血栓栓子近距离外观显示分层结构，这是骨盆或下肢大静脉血栓的特征表现。
