In this important (albeit short) soliloquy at the end of Act 2, Scene 1, Tranio shares vital information with the audience, informing them of his plan to improve Lucentio's station in the eyes of Bianca and her father:
TRANIO: A vengeance on your crafty withered hide!
Yet I have faced it with a card of ten.
'Tis in my head to do my master good.
I see no reason but supposed Lucentio
Must get a father, called “supposed Vincentio”—
And that’s a wonder. Fathers commonly
Do get their children. But in this case of wooing,
A child shall get a sire, if I fail not of my cunning.
This soliloquy brings the audience into the loop, foreshadowing the fact that Tranio will later attempt to bring in an actor to play Vincentio. In a comedic play like The Taming of the Shrew, foreshadowing is often more of a direct reference to future actions than a murky insinuation about cosmically fated events. Shakespeare did not choose to mix comedy with tragedy, or history, or pure drama in this play, but chose the principally comedic route; as such, he does not need to build suspense through foreshadowing, and can deploy this device with slightly less subtlety.