Adventure at sea

6 anni fa

Hello!
Use only one word in each gap!

I've been thinking a lot on #16, #18, #20 and #22. I can't possibly crack it.
#18
Being the (17) only human survivor, he finds (18) ........................ sharing a lifeboat with a menagerie of creatures, includingi a hyena, a zebra, an orang-utan and a 200 kg Bengal Tiger.
In #18 possible doesn't make sense becaus it should have a  subject, like "it is possible".
Could you give me a clue oe something? I am trying to figure it out myself.

Thank you!