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 first essential in elephant training is to assign to the animal a single mahout who will be entirely responsible for the job.
驯象中至关重要的是指派一名专门的驯象员,全面负责这项工作。