Definition
回火 is a technical separable verb (离合词) with two main senses: (1) in metallurgy, to temper metal (heat treatment to reduce brittleness); (2) in mechanics, to backfire (an engine misfiring with a loud bang). As a v.o. word, it can be separated: 回了一次火 ('did tempering once'). The 回 (huí) acts as the verb, and 火 (huǒ) as the object, allowing insertion of measure words or aspects between them.
v.o.
temper (metallurgy, heat treatment)backfire (engine/vehicle misfire)
Examples
- 回火。Zhè zhǒng gāng xūyào jīngguò huí huǒ chǔlǐ cáinéng biàn yìng.This type of steel needs to undergo tempering to become hard.
- 回火，。Qìchē fādòngjī tūrán huí huǒ le, xià le wǒ yí tiào.The car engine suddenly backfired and startled me.
- ，。Shīfu huí le yí cì huǒ, gōngjiàn jiù hégé le.The master tempered it once, and the workpiece was qualified.
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