多项选择题 Strategies can be divided into（）.

多项选择题 The problem solving can be divided into three states（）

判断题 Problem solving is thinking that is directed toward the solving of a specific problem that involves both the formation of responses and the selection among possible responses.（）

多项选择题 What are the stages of language development in vygowski’s theory.（）

单项选择题 The following concepts do not belong to Piaget’s Theory（）.