correct language in documentation (#29502)

(cherry picked from commit 37dc16e)

doc/src/base/base.md

@@ -44,14 +44,14 @@ This is the list of reserved keywords in Julia:
 `return`, `struct`, `true`, `try`, `using`, `while`.
 Those keywords are not allowed to be used as variable names.
 
-The following two word sequences are reserved:
+The following two-word sequences are reserved:
 `abstract type`, `mutable struct`, `primitive type`.
 However, you can create variables with names:
 `abstract`, `mutable`, `primitive` and `type`.
 
 Finally `where` is parsed as an infix operator for writing parametric method
 and type definitions. Also `in` and `isa` are parsed as infix operators.
-Creation of variable named `where`, `in` or `isa` is allowed though.
+Creation of a variable named `where`, `in` or `isa` is allowed though.
 
 ```@docs
 module