秒表

zhè ge jiào shī hái tōng guò miǎo biǎo hé fēng míng qì yàn zhèng le zhè ge shì shí

这个教师还通过秒表和蜂鸣器验证了这个事实。

The teacher also demonstrated with a stopwatch and a buzzer.

shù zì miǎo biǎo

数字秒表

digital stopwatch