Then thus to Ráma trained and tried In battle King Sugríva cried: “Come, Hanumán’s broad back ascend; Let Angad help to Lakshmaṇ lend. These high above the sea shall bear Their burthen through the ways of air.”

In plain words: King Sugriva tells Rama to climb on Hanuman's broad back, and says Angad will carry Lakshmana. The two monkeys will carry them through the air above the sea.