并列题名：I didn't know that whales can sing I didn't know that whales can sing 并列题名：I didn't know that chimps use tools 并列题名：I didn't know that dinosaurs laid eggs 并列题名：I didn't know that some birds hang upside down 并列题名：I didn't know that crocodiles yawn to keep cool 并列题名：I didn't know that 并列题名：I don't know how she does it 并列题名：Island that can sing 并列题名：I didn't know that some bugs glow in the dark