Transcript:
They have a tough mission ahead.
Thousands of members of the Saudi security forces have been taking part in a parade ahead of the world's biggest religious gathering.
The Hajj involves over 2 million Muslim pilgrims.
With tensions simmering in the region, particularly in Lebanon and Syria, the logistics are even more complicated than usual.
Vocabulary:
mission n. 使命,任务
parade vt. 游行,炫耀,列队行进
pilgrims v. 去朝圣;漫游
simmering vt. 慢煮
logistics n. [军] 后勤,后勤学,物流