Inaudible means unable to be heard.
I have never heard of this word, so cannot suggest any sentence, it isn't in my dictionary.
one
Yes, it is one word, the verb or adjective overheard.
'Time'.
Cannot is correct. Can not is incorrect.
Breathe has only one pronunciation that I have ever heard or heard of.
There is no such word - yet.There is no such word as 'prompently' . I cannot even think of one close to that spelling. This is why they print Dictionaries.There is no such word as 'prompently' . I cannot even think of one close to that spelling.
There is no such word as 'lemychal' . I cannot even think of one close to that spelling.There is no such word as 'lemychal' . I cannot even think of one close to that spelling.
The base word for the word "heard" is "hear."
The correct spelling is one word, cannot. The contraction of cannot is can't.
A word for "which cannot be solved" is unsolvable.