One of the most common mistakes is to use an adjective ending in -ed or -ing without realising on the difference in meaning.
Some adjectives accept both forms but:
– Adjectives ending in -ed are used to express how a person feels. ex. I am bored.
– Adjectives ending in -ing are used to express how a situation is. ex. This class is boring.
Look at the following slides for more examples:
Click HERE and see some of these adjectives. Below you have an exercise to practise. Good luck!