Someone (machi-) talks with a spirit being (-en) or vice versa.
Ivv. sisirinyen 'to talk to; to greet'
Machisisirin si āmang di simna āpong lakay.
Father talks with (the spirit of) deceased grandfather.
Sisirinen yaten no Dyos.
God talks with us.
Someone (ma-), especially a child, can begin to understand speech.
Masisirin danaw anak naw.
His child can already begin to understand speech.