interleave [interleaved, interleaving, interleaves](to intersperse (something) at regular intervals between the parts of a thing) verb [UK: ˌɪn.tə.ˈliːv] [US: ˌɪn.tər.ˈliːv]
intersperse [interspersed, interspersing, intersperses](to mix two things irregularly) verb [UK: ˌɪn.tə.ˈspɜːs] [US: ˌɪn.tər.ˈspɝːs]