shí / yàn / kāi / shǐ / qián / qǐng / què / rèn / dǎo / xiàn / jiē / zài / zhèng / què / de / zhèng / jí / shàng

实验开始前，请确认导线接在正确的正极上。

Before starting the experiment, make sure the wire is connected to the correct positive electrode.