 Studying Macbeth, here's how you can analyse Banco's growing doubts about Macbeth in Act 3, Scene 1. Banco is alone and he reflects that Macbeth has to now. King Cordo Glamis. Shakespeare's use of Cesura here as well as the Rule of Three show that Banco is wondering whether Macbeth has done something to become powerful this quickly. He says, I fear thou placed most folly for it. In other words, he's worried that Macbeth is the one that actually did the killing and the litteration of F as well as the reference to Fowl echoes the witch as an Act 1, Scene 1, who said Fowl is fair and fair as Fowl. But he also remembers that the witch is prophesised about his children and we can see that Banco kind of hopes that his kids will also be kings. This rhetorical question further emphasises his hope that his children will be kings. Yet this exclamatory sentence shows he's going quiet because he sees Macbeth as approaching. What this is illustrating is that he can't trust Macbeth anymore.