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。
In the first place, any scientific study requires that there be no preferential weighting of one or another of the items in the series it selects for its consideration.
首先,任何科学研究都要求人们对可供考虑的诸多因素不能厚此薄彼,偏向某一方面。