You can join words, clause or oh phrase with them. They make your writing flow much more smoothly. Read this example:
I met a grumpy fairy. She gave me a wish. I wished for wings. The wings appeared. They were useless. They were shimmery. They were sparkly. They wre fairy-sized. They were also stuck to my shoulders. "You wished for wings. You got them," snapped the fairy. The fairy disappeared.
It's a bit jerky, isn't it?
Try this instead:
I met a grumpy fairy. She gave me a wish, so I wished for wings. The wings appeared but they were useless. They were shimmery and sparkly and fairy-sized.They were also stuck to my shoulders. "You wished for wings. You got them," snapped the fairy and disappeared.
Get Co-ordinated
Thewords 'and', 'nor', 'but', 'or', 'yet' and 'so' are known as co-ordinating conjunctions. You use them to join words, sentences, or parts of sentences that are equally important. For example, 'cats like to miaow.' and, 'Dogs like to bark.' are equally important, so you can connect them with a co-ordinating conjunction, like this:
Cat like to miaow, and dogs like to bark.
Or like this:
Cat like to miaow, but dogs like to bark.
You can often change the meaning of a sentence with the conjunction you choose, like this:
Cats like to miaow, so dogs like to bark.
This would mean that dogs like to bark because cats like to miaow.
Grammar Guidance
If you are joining two sentences that contain the same noun, you can take the second noun away to avoid repetition. For example, if you join, 'The toddler fell over' with, 'The toddler started bawling' you can say:
The toddler fell over and started bawling.
Rather than:
The toddler fell over and the toddler started bawling.
Grammar Extra
Usually, it's best to avoid starting a sentence with a conjunction, especially if you are writing a formal letter or if you're doing school work. However, it is perfectly all right to start a sentence with 'and' or 'but' in stories or in informal writing. You will probably notice that lots of writers use these words for dramatic effect and for emphasis. And you can, too! It can work well so long as you don't overdo it.


Conjunction Extras
There are three other types of conjunction as well as co-ordinating conjunctions. These are:
Subordinate
Subordinate conjunctions join the more important clause to the less important clause-its subordinate. They are words such as 'although', 'as', 'because', 'since', 'unless' and 'while'. For example, 'I'm tired' and 'I slept well' can be joined together, but the fact that you are tired is more important, so that conjunction you should use is a subordinate conjunction:
I'm tired although I slept well.
Correlative
Correlative conjunctions come in pairs-they 'correlate', which means that they compare things. They are words such as 'not only ... but also', ' either ... or' and 'neither ... nor', like this:
He is not only annoying but also my brother.
He is neither clever nor funny.
He is either shouting or pinching.
Whether I am alone or with friends he gets on my nervers.
Compound
Lastly, compound conjunctions are made up of more than one word, such as 'so that' or ' as soon as':
I will stay in my bedroom as long as I like.
I am hiding so that he won't find me.
I will come out as soon as they have gone.
OH!
'Oh!' and other words like it are known as interjections, or exclamations. They are words or phrases that appear by themselves with exclamation mark - often as a warning or to show emotion. You might see them on signs in a safari park or near a school:
Elephants! Please stay in your car.
Slow! Children crossing.
You can use interjections in your own writing to slow how someone is feeling - 'Oh yes!', ' Wow!' Thy can also make great sound effects -' Pop!', 'Blurrrgh!' "Wheeeee!' Used well and sparingly, interjections can liven up your writing, but- hey!- do not overuse them. Otherwise, people may not pay attention when you use them as commands, as in, 'Go!', 'Help!' 'Listen!' and 'Stop!'
To Be Continue...