• Comparatives: As/As

• Read and listen. Listen again and repeat.
• 
• Use as + adjective/adverb + as to make comparisons between things that are equal in some way.

• The new monitor is as big as my TV.

  Tim works as hard as Roy.

• 
  

  Use not as + adjective/adverb + as to make comparisons between things that are not equal.

• The new program is not as good as the old one.

  The new program does not operate as well as the old one.

Source : Alison