Fix grammatical errors in docstrings

music21/common/stringTools.py

@@ -310,7 +310,7 @@ def stripAccents(inputString: str) -> str:
     >>> common.stripAccents('Süss, “êtré”')
     'Suss, "etre"'
 
-    Note -- is is still possible to have non-Ascii characters after this,
+    Note -- it is still possible to have non-Ascii characters after this,
     like in this Japanese expression for music:
 
     >>> common.stripAccents('音楽')

music21/corpus/__init__.py

@@ -88,7 +88,7 @@ def getCorePaths(
     expandExtensions=True
 ) -> list[pathlib.Path]:
     '''
-    Get all paths in the corpus that match a known extension, or an extenion
+    Get all paths in the corpus that match a known extension, or an extension
     provided by an argument.
 
     If `expandExtensions` is True, a format for an extension, and related

music21/roman.py

@@ -1313,7 +1313,7 @@ class Minor67Default(enum.Enum):
     >>> vi('VI', roman.Minor67Default.CAUTIONARY)
     'A- C E-'
 
-    Whereas `QUALITY` follows a strict interpretation of what preceeding sharp and flat
+    Whereas `QUALITY` follows a strict interpretation of what preceding sharp and flat
     signs mean.  With `QUALITY`, since vi is already sharpened, #vi raises it even more.
     And since VI is already flattened, bVI lowers it even further:
 

music21/scale/__init__.py

@@ -25,7 +25,7 @@
 and :class:`~music21.scale.RagMarwa`.
 
 All :class:`~music21.scale.ConcreteScale` subclasses provide the ability
-to get a pitches across any range, get a pitch for scale step, get a
+to get pitches across any range, get a pitch for scale step, get a
 scale step for pitch, and, for any given pitch ascend or descend to the
 next pitch. In all cases :class:`~music21.pitch.Pitch` objects are returned.
 
@@ -155,7 +155,7 @@ def isConcrete(self):
         '''
         To be concrete, a Scale must have a defined tonic.
         An abstract Scale is not Concrete, nor is a Concrete scale
-        without a defined tonic.  Thus, is always false.
+        without a defined tonic.  Thus, it is always false.
         '''
         return False
 

music21/stream/base.py

@@ -113,7 +113,7 @@ class Stream(core.StreamCore, t.Generic[M21ObjType]):
     Stream can have its own offset, when Streams are
     embedded the offset of an element is relatively only
     to its parent Stream. The :meth:`~music21.stream.Stream.flatten`
-    and method provides access to a flat version of all
+    method provides access to a flat version of all
     embedded Streams, with offsets relative to the
     top-level Stream.