What's the verb form of lightning?

Well, that person better C sharp or he’ll B flat.

Weird. This is the second time today I’ve read that on the 'tubes. Which brings the total of times I’ve read that up to two.

If someone’s struck by a falling piano, it’s pretty sure he won’t be upright.

“It is lightening/It lightened”. True, that’s the same word as “to get lighter”, but this is hardly the only such instance in English.