Many school buildings are unsafe, and some are falling apart.许多校舍不安全，有些简直是摇摇欲坠。Dangerous undertows make swimming unsafe along most of the coastline.由于存在着危险的下层逆流，在大部分海岸线附近游泳都不安全。Critics claim the trucks are unsafe.批评家声称这些...
Dangerous undertows make swimming unsafe along most of the coastline.由于存在着危险的下层逆流，在大部分海岸线附近游泳都不安全。The ice on that pond is unsafe for skating.在那个池塘的冰面上溜冰不安全。In the larger neighbourhood, I felt very unsafe.在大一点的小区里，我感到很不安全...