lǎo / shī / yòng / rán / shāo / chí / yǎn / shì / le / jīn / shǔ / fěn / mò / zài / yǎng / qì / zhōng / de / rán / shāo

老师用燃烧匙演示了金属粉末在氧气中的燃烧。

The teacher used a combustion spoon to demonstrate the burning of metal powder in oxygen.