The picture displays the evolution of cutting tools in the Stone Age from 1.4 million years ago to 0.8 million years ago. 
Overall
, Linking Words
it is clear that
 the instrument has not only been sharp but  Linking Words
also
  wide and well-sized.
On the one hand, it was seen that 1.4 million years ago  Linking Words
Tool
 A had a blunt peak from the front Use synonyms
view
. Use synonyms
However
, the side Linking Words
view
 of  Use synonyms
Tool
 A  seemed flatter than the front and back views. Meanwhile, the back Use synonyms
view
 of the Use synonyms
Tool
 A has a sharp edge. 
Use synonyms
On the other hand
, Linking Words
Tool
 B had some massive progress during the period. Use synonyms
Similarly
, it can be seen that the front Linking Words
view
 of Use synonyms
Tool
 B had a sharp edge compared to Use synonyms
Tool
 A. Use synonyms
Likewise
, the side Linking Words
view
 had Use synonyms
also
 become flat and thinner than that of Linking Words
Tool
 A. Use synonyms
In contrast
, the back Linking Words
view
 of  Use synonyms
Tool
 B had gained size and it was growing wider than Use synonyms
Tool
 A.Use synonyms