doc: fixed small errors

Closes #88
https://github.com/cuelang/cue/pull/88

GitOrigin-RevId: ea72847a3a1b0314372f3eb6746688716ff0100c
Change-Id: I4093e992283d4f28aa13274f63e9dbedcb32c091
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/3047
Reviewed-by: Marcel van Lohuizen <mpvl@google.com>
diff --git a/README.md b/README.md
index b885dc7..b937228 100644
--- a/README.md
+++ b/README.md
@@ -46,7 +46,7 @@
 ### How?
 
 CUE merges the notion of schema and data.
-The same CUE defintion can simultaneously be used for validating data
+The same CUE definition can simultaneously be used for validating data
 and act as a template to reduce boilerplate.
 Schema definition is enriched with fine-grained value definitions
 and default values.
diff --git a/doc/ref/impl.md b/doc/ref/impl.md
index 59a1ca6..ca38ef2 100644
--- a/doc/ref/impl.md
+++ b/doc/ref/impl.md
@@ -139,7 +139,7 @@
 
 References in expressions refer to other nodes within the `C` and represent
 a copy of the substructure `C'` of `C` rooted at these nodes.
-Any references occuring in terms assigned to nodes of `C'` are be updated to
+Any references occurring in terms assigned to nodes of `C'` are be updated to
 point to the equivalent node in a copy of `C'`.
 <!-- TODO: define formally. Right now this is implied already by the
 definition of evaluation functions and unification: unifying