There are many difficulties in primary school mathematics, some of which include: the meaning and nature of fractions, the concepts and meanings of decimals and cyclic decimals, addition and subtraction of decimals, multiplication and division of decimals, and reciprocity of integers, fractions and decimals; The meaning of four operations and the relationship between the parts of addition, subtraction, multiplication and division; The order of the four operations; Use letters to represent numbers; Simple arrangement and combination; Solve simple equations or something.

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