It's all one syllable.
The word joint has one syllable. This means the whole word is the syllable and so there are no syllable breaks.
The word sand only has one syllable. This means the whole word is the syllable and so there are no syllable breaks.
The stress on a syllable can be called an accent.
You separate the syllables with a hyphen.
mor-ning
There isn't a final syllable in the word called. The word called is only one syllable. The -ed may make it sound like another syllable but it isn't.
There are 2 syllables. Bus-ness.
The word "league" is separated into one syllable: lea-gue.
Yes, you can use a hyphen in a three-syllable word to separate its component parts or to indicate a compound adjective.
Yes. dou-ble Just remember, if it sounds like two syllables, and you separate them, each syllable MUST have a vowel in it.
One-syllable words are called monosyllables.
The term for skipping a syllable is called "elision." It refers to the omission of a sound or syllable when speaking.