It divided surface similarity into ac surface similarity and CD surface similarity in this research. It adopted homemade analogical test to examine the mechanism of surface similarity in analogy.

本研究把源问题与靶问题之间的表面相似性区分为ac项表面相似性和CD项表面相似性，采用自制的类比推理测试题，考察了表面相似性促进类比推理的机制。

youdao

Two AC-130s have been recently lost - one was shot down by a surface-to-air missile, another crashed in Somalia when, it is thought, a round accidentally exploded.

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