clearances
Clearance is the removal of old buildings, trees, or other things that are not wanted from an area.
a slum clearance operation in Nairobi.
清拆内罗毕贫民窟的一次行动。
The UN pledged to help supervise the clearance of mines.
联合国承诺帮助监督扫雷工作。
If you get clearance to do or have something, you get official approval or permission to do or have it.
Thai Airways said the plane had been given clearance to land.
泰国航空公司说该飞机已经被授予了着陆的官方许可。