The correct spelling is curiosity.
Some example sentences with the word are:
I will satisfy my curiosity.
The kitten's curiosity got the better of him.
What began as a curiosity turned into a major scientific discovery.
If Marcus spelled 20 out of 25 words correctly then he spelled 80% of the words correctly.
The words you are looking for, cold and catarrh, are spelt correctly in the question.
The difference between the two words is that they are both spelt differently - though neither are spelt correctly - the correct spelling is Autumn.
Daydreaming can either be spelt as one word or two, if you wish it to be spelt as two words you have spelt it correctly, but if you wish it to be a single word, as it is usually seen, it would be written daydreaming.
The correct spelling of the word is incidentally.Some example sentences are:Incidentally, we have some evidence putting you at the scene.He incidently turns out to be my half brother.
It is spelt two.
its spelt whole.
The number 2 is spelt 'two'.
Think if it as two words - Con Air. In other words it is pronounced as it is spelt.
The two words are spelt as you have done in the question.
Can be spelt either way.
The word "hardworking" can be spelt as a single word or as two words.