Bear is the root word of unbearably.
Unbearably has four syllables. The syllables are un-bear-a-bly.
The word unbearably consists of five syllables - un-bear-a-bly.
Sure, I can use "so" at the beginning of a sentence.
4
bear
So- you are asking when to use 'when' in a sentence. When you are asking how to use when in a question, you are already using when in a sentence, because a question actually is a sentence. I like to use when in a sentence whenever I like.
"Can you use cruel in a sentence?" is a sentence, so yes, unless you mean something else?
'Bisters' is not a word, so I can't use it in a proper sentence.
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Unbearably hot.
Sentence: The cost of living in 2008 for France was so and so...