The officers, as usual, lived in twos and threes in the roofless, half- ruined houses.
She was working recently with the number forty, when I said to her, "Make twos."
A flower in which the parts are arranged in twos is called dimerous; when the parts of the whorls are three, four or five, the flower is trimerous, tetramerous or pentamerous, respectively.
She replied immediately, "Twenty twos make forty."
Respectful Parenting From Birth Through the Terrific Twos which won the 2007 IPPY National Gold Medal in the parenting category.