经过长时间使用，钨丝会变细，电阻就会变大，所以灯泡也就变暗了。

经过长时间使用，钨丝会变细，电阻就会变大，所以灯泡也就变暗了。

Results (English) 1:

After prolonged use, the tungsten wire becomes thin, the resistance becomes large, so that the lamp also darkened.

Results (English) 2:

After a long period of use, the tungsten wire will become thinner, the resistance will become larger, so the bulb will also darken.

Results (English) 3:

After a long time of use, the tungsten wire will be thinner and the resistance will be larger, so the bulb will be dimmed.