is about to :
     ὁ λύκος μέλλει τοῖς μήλοις ἐμπίπτειν
ἐγὼ μέλλω καθεύδειν 
(it's past 23:00, I'm tired)
 τί μέλλεις ποιεῖν (father to 13 year old trying to sneek out of the house at midnight)
  μέλλει βοᾶν τε καὶ κεντεῖν τοὺς βοῦς ἀγρίως (He's about to shout and goad them fiercely when he sees the big obstructing stone)
  μέλλομεν περαίνειν τὸ μάθημα. (finish the lesson, we ARE about to, really!)
 
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