Here are four different ways to say the sentence: "Once an echidna has dug itself into the ground, a hungry predator will have only its spines to attack."
- After the echidna buries itself in the dirt, the only thing a hungry animal can get to are its sharp spines.
- When an echidna digs into the ground, hungry predators can only try to bite its spiky body.
- Once the echidna hides underground, predators can attack only its sharp spikes.
- An echidna that digs into the earth protects itself because the predator can only reach its pointed spines.