I was startled by a sudden noise.
All of a sudden a wild badger attacked me.
All of a sudden I found that I had written a sentence in reply to a question.
all of a sudden.......
The bus stopped with a sudden jolt.
Her impulse to shop was starting to take over her whole life. Another good sentence would be, she had a sudden impulse to buy the expensive purse.
It is called an exclamatory sentence.
She politely declined the invitation to the party.
Caught in a sudden downpour, we were absolutely drenched. She looked absolutely beautiful on her wedding day. He was absolutely positive that he had locked the front door.
"A sudden flash of light in the night sky." That isn't a sentence at all, since it has no predicate (verb).
a sudden storm
The sentence should begin with the definite article 'the.
Outwardly serene, his emotions boiled.His sudden reaction surprised everyone, as he was always so outwardly charming.