a tug of war contest的用法和样例：
- The tug of war ended when both teams tumbled in a heap.
- In Japan,a tug of war of super thick rope competition is held every autumn.
- At every Dragon and Boat Festival,Tanggang town of Taiwan holds a tug of war competition across the banks.
- Clearly a tug of war over key policies continues between the pragmatic and ideological camps.