The given diagram illustrates the improvement of cutting tools in the 
Stone
 Age. Use synonyms
Overall
, the given diagram witnessed significant changes Linking Words
about
 tools' views Change preposition
in
except
 their heights in 6 million Add the preposition
except for
years
. 
Begin with Use synonyms
Tool
 A, Use synonyms
this
 Linking Words
have
 3 views of Change the verb form
has
stone
 which were used Use synonyms
Change preposition
for cutting
cutting
 purposes Change preposition
for cutting
Change preposition
apply
in 
1.4 million Change preposition
apply
years
 ago. The Use synonyms
tool
 was 5 cm Use synonyms
height
 and Change preposition
in height
have
 Wrong verb form
had
copped
 Correct article usage
a copped
shape
. In terms of Use synonyms
Tool
 B, Use synonyms
this
 Linking Words
have 
Unnecessary verb
apply
also
 3 views about Linking Words
stone
 and Use synonyms
this
 cutting Linking Words
stone
 noticeably dramatically changed and reached more architectural illustration. 
In Use synonyms
view
 of Use synonyms
front
, Correct article usage
the front
Tool
 A Use synonyms
getting
 bigger and Wrong verb form
got
getting
 a diamond Wrong verb form
got
shape
 over the given 6 million Use synonyms
years
. Use synonyms
Tool
 B, in Use synonyms
side
 Correct article usage
the side
view
, Use synonyms
getting
 thicker and sharper in the given time period. In terms of Wrong verb form
gets
back
 Correct article usage
the back
view
, Use synonyms
Tool
 A Use synonyms
were 
resembled of triangle Unnecessary verb
apply
shape
 and changed in Use synonyms
years
 and Use synonyms
finally
 Linking Words
reach
 and diamond Wrong verb form
reached
shape
 like its front Use synonyms
view
.
Use synonyms
Tool
 Use synonyms
A's
 and Change noun form
A
Tool
 Use synonyms
B's
 which Change noun form
B
used
 for cutting aims, have Add a missing verb
are used
same
 heights in the given time periods, at 5 cm for both.Correct article usage
the same