The present participle of most verbs has the form base+ing. It is used in many different ways.
THE PRESENT PARTICIPLE AS PART OF THE CONTINUOUS FORM OF A VERB
I am working.
He was singing.
They have been walking.
We will be staying.
She would have been expecting me.
THE PRESENT PARTICIPLE AFTER VERBS OF MOVEMENT & POSITION
This construction is particularly useful with the verb to go.
She went shopping.
I go running every morning.
He lay looking up at the clouds.
She came running towards me.
THE PRESENT PARTICIPLE AFTER VERBS OF PERCEPTION
The pattern for this usage is verb + object + present participle. There is a difference in meaning when such a sentence contains a zero infinitive rather than a participle. The infinitive refers to a complete action while the present participle refers to an ongoing action.
I heard someone singing.
He saw his friend walking along the road.
I can smell something burning!
I watched the birds flying away.
THE PRESENT PARTICIPLE AS AN ADJECTIVE
It was an amazing film.
Dark billowing clouds often precede a storm.
He was trapped inside the burning house.
Many of his paintings show the setting sun.
THE PRESENT PARTICIPLE WITH THE VERBS SPEND AND WASTE
The pattern with these verbs is verb + time/money expression + present participle.
My boss spends two hours a day travelling to work.
Don't waste time playing computer games!
They've spent the whole day shopping.
I wasted money buying this game.
THE PRESENT PARTICIPLE WITH THE VERBS CATCH AND FIND
The pattern with these verbs is verb + object + present participle. With catch, the participle always refers to an action which causes annoyance or anger. This is not the case with find, which is unemotional.
If I catch you stealing my apples again, there'll be trouble!
Don't let him catch you reading his letters.
I caught him going through my bag.
We found some money lying on the ground.
They found their mother sitting in the garden.
THE PRESENT PARTICIPLE FOR TWO ACTIONS AT THE SAME TIME
When two actions occur at the same time, and are done by the same person or thing, we can use a present participle to describe one of them. When one action follows very quickly after another done by the same person or thing, we can express the first action with a present participle.
Whistling to himself, he walked down the road. = He whistled to himself as he walked down the road.
They went laughing out into the snow. = They laughed as they went out into the snow.
Dropping the gun, she put her hands in the air. = She dropped the gun and put her hands in the air.
Putting on his coat, he left the house. = He put on his coat and left the house.
THE PRESENT PARTICIPLE TO EXPLAIN A REASON
The present participle can be used instead of a phrase starting with as, since, or because. In this usage the participial phrase explains the cause or reason for an action.
Feeling hungry, he went into the kitchen and opened the fridge.
Being poor, he didn't spend much on clothes.
Knowing that his mother was coming, he cleaned the flat.
He whispered, thinking his brother was still asleep.