The channel is only a few centimeters in diameter, but that is wide enough for electrons to follow the channel to the ground in the visible form of a flash of lightning.
这个通道的直径只有几厘米，但它的宽度足以让电子以闪电这样看得到的形式随着通道到达地面。
2
Emergents, which do not form a continuous layer, are usually the giants of the forest, reaching heights of 35 to 70 m or more, and trunk sizes of over 2 m in diameter.
不形成连续层的新生植物通常是森林中的巨人，高度可达35至70米或更高，树干直径超过2米。
3
The ultrathin wires, several nanometers in diameter, can be combined to form high-power electrodes for lithium-ion batteries like those used in many modern electronics.