Both adjectives and adverbs describe other words.

• 
  Adjectives describe a noun or pronoun.
  
• 
  Adverbs describe a verb, adjective, or other adverb.
  

Tip: Many adverbs are formed by adding -ly to an adjective (poor →poorly; gentle → gently), but a number of common adverbs do not follow this pattern.

Further, some words can be either adjectives or adverbs, depending on how they are used in a sentence.

There are a large number of adjectives ending in '-ing'. Most of them are related in form to the present participles of verbs. In this grammar they are called '-ing' adjectives.

• He was an amiable, amusing fellow.
• He had been up all night attending a dying man.