They've promised to keep both we quality and the quantity of the 300 bicycles in conformity with the contract stipulations.
他们已承诺那300辆自行车的质量和数量一定与合同规定相吻合。
The spheres had been magnetized and attracted or repelled each other all the time.
金属球经过磁化,互相之间不停地相互吸引或相互排斥。