be

English speakers use this tiny word every minute, but it is really a grammatical Frankenstein. Old English had a b-verb, beon, while the am/was forms came from a different old family altogether; later English mashed them into one super-irregular verb. That b-verb goes back to Proto-Indo-European *bheue-, the same deep ancestor behind German bin and bist, Old Church Slavonic byti, Lithuanian būti, and even Greek and Latin relatives that circle the idea of coming into existence. So when you say be, you are using a word whose history is less a straight line than a scrapyard assembled into a vital machine. It is the one verb that can simply stand there and still carry the whole sentence on its back.