This study is on the mathematical cognition of MD, that includes count, quantity conservation, space-time conception, logic conception, calculation and manipulation.

该研究采用测验法，考察数学学习不良(MD)儿童的早期数学认知能力，包括计数、数守恒、时空概念、逻辑、计算和操作等方面。

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Even if you do not count the large quantity of bonds issued by telecoms companies that are now bust or nearly so, the average junk issue trades at a yield of some ten percentage points above Treasury bonds.

ECONOMIST: Signs of a crunch in America's markets for credit