n.乌合之众;流氓地痞;不三不四的人

The city's riffraff often congregate in the park after dark.
这座城市的三教九流人士常在天黑后聚集在公园里。
The police had to clear the square of riffraff before the royal visit.
在王室访问前，警察必须清理广场上的闲杂人等。
She tried to avoid the riffraff at the party by sticking to the VIP area.
她试图待在贵宾区以避开派对上的乌合之众。
The store's security guards were on high alert, watching out for any riffraff.
商店的保安高度警觉，留意任何可能的不法分子。
In the old days, the harbor was filled with the riffraff of sailors and smugglers.
往昔，港口满是水手和走私贩的混杂人群。
The politician's speech was aimed at appealing to the working-class riffraff.
那位政治家的演讲旨在吸引工人阶级的普通民众。
The concert was disrupted by a group of rowdy riffraff who refused to follow instructions.
音乐会因为一群闹事的不良分子拒绝遵守规定而被打断。
The neighborhood used to be a haven for riffraff, but recent developments have gentrified the area.
这个社区以前是不良分子的藏身之处，但最近的发展使其变得高尚起来。
The festival organizers had to limit entry to prevent the event from being overrun by riffraff.
为了防止活动被乌合之众淹没，节日组织者不得不限制入场人数。
The boss doesn't want any riffraff applying for the job, only candidates with top-notch qualifications.
老板不希望有任何资质平庸的人申请这个职位，只考虑顶级资质的候选人。