Were you taught anything in school that you had to unlearn? As kids, we're probably all taught about the joys of the word 'Suddenly!'. Sticking it at the front of a sentence is the best way to denote something happening quickly - or not. In fact, it wasn't until I started writing novels that I realised just how backhanded the word is.
Now, I'm sure by now most of you have had the same realisation. While the word isn't completely useless (I find it works well as an adverb before a verb, rather than a standalone adverbial phrase), there are much more effective ways to express the speed that events are taking place in your story.
Writing sudden events can be tricky, but I've done my best to compile a list of methods that you can use to help really convey immediacy in your scenes.
Show, Don't Tell
This rule applies to so many aspects of writing (I may do an entire post on the subject!), and conveying sudden events is no different. In real life, things can often happen so quickly that we don't have time to process them.
That being said, the same can apply in your writing. Focus on the effects of the action, rather than the action itself. This will give the effect that the action was too quick be seen. Don't be afraid to cut characters off mid-thought, mid-narration, or mid-dialogue too
Forget setting up for the event. Don't let the reader see it coming; simply launch into the action by writing in its initial effect in a single, concise sentence. Just as you would if you were to right 'Suddenly, the door opened,' get rid of 'suddenly' and simply write, 'The door opened.'
Take this example from Harry Potter and the Goblet of Fire by J. K. Rowling:
There was silence. He stared all around him. What had happened to her? Her scream seemed to have come from somewhere ahead. He took a deep breath, and ran through the enchanted mist. The world turned upside-down. Harry was hanging from the ground, with his hair on end, his glasses dangling off his nose, threatening to fall into the bottomless sky.
As you can see, rather than describing the sensation of being turned upside-down in detail, Rowling summed up the effect in four words, reducing any slow in pacing from Harry running, to the sky and ground reversing. Only once the reader knows what event has occurred does she go into the consequences, mentioning Harry's hair and glasses.
Use words that connote speed. Avoid adverbs, instead opting for verbs that already imply speed. For example; 'He ran across the room,' becomes, 'He shot across the room.'; 'She turned around,' becomes, 'She spun around.'; 'My eyes moved to the door,' becomes 'My eyes darted to the door.'
Here's another example from Harry Potter and the Goblet of Fire:
Before Voldemort could stick his snake-like face around the head-stone, Harry had stood up ... he gripped his wand tightly in his hand, thrust it out in front of him, and threw himself around the headstone, facing Voldemort.
Particularly, look at the words 'thrust' and 'threw'. Rowling could have simply said 'Harry held his wand out in front of him' and 'moved himself around the headstone,' but by using thrust and threw, Rowling successfully translated force and speed into Harry's movements.
Use plosive language. These are words that have a sudden stop and start of air when you speak them. They are explosive sounds that can help to connote explosive movements. For example; shot, bit, cut,