Idiom:

No spine 没有勇气，胆小鬼

Hit the book:

Adventurous
Towering
Penguin
Infectious
Immune system
Isolation
Pathogen
Simultaneously

For those who go, it's the trip of a lifetime – and it wouldn't be complete without a selfie with penguins. But growing tourism to the Antarctic, in combination with its warming climate, could be placing penguins at a risk of infectious disease