Avoiding mistakes: it, is, it's or its?

Exercise created by Tereza Neves

Fill in all the gaps, then press "Check" to check your work.

Fill in each gap with one of the following options from the dropdown list:

it - pronoun used to refer to an animal or thing, and as subject of an impersonal verb
is - third person singular of the present simple of the verb to be
it's = it + is
its - possessive pronoun or determiner

The great thing about couch surfing that allows you to travel cheaply and make lots of friends.

The octopus a master of disguise; first line of defense ability to match the colors, patterns, and even textures of surroundings. When discovered, an octopus will release a cloud of black ink to obscure attacker's view, giving time to swim away.

The new solar-powered computer, which has a solar pannel embedded in lid, will be the first of kind.
All the explorer's maps were lost in the shipwreck, so now impossible to know where the treasure .

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Everybody thinks Frank's fault, but they're wrong. He had nothing to do with .

Peanut butter