- The spring is the high-frequency time in one year,with higher accident frequency than Summer & Autumn.
- The roadside accident frequency is higher in mountainous area highway,this is concerned with lacking protection facilities.
- The identification and improvement of black-spot, as an important task of traffic safety management, are very effect measures to reduce the traffic accident frequency.
- Stand tanks, spherical vessels and cylinder vessels, reactors are special facilities which are widely used in national produce, also, they have high accident frequency.
- I saw the whole accident with my own eyes.
- The accident put an untimely end to the party.