Update noteworthy-differences.md (JuliaLang#40326)

They to there

doc/src/manual/noteworthy-differences.md

@@ -240,7 +240,7 @@ For users coming to Julia from R, these are some noteworthy differences:
   * In Julia, the standard operators over a matrix type are matrix operations, whereas, in Python, the standard operators are element-wise operations. When both `A` and `B` are matrices, `A * B` in Julia performs matrix multiplication, not element-wise multiplication as in Python. `A * B` in Julia is equivalent with `A @ B` in Python, whereas `A * B` in Python is equivalent with `A .* B` in Julia.
   * The adjoint operator `'` in Julia returns an adjoint of a vector (a lazy representation of row vector), whereas the transpose operator `.T` over a vector in Python returns the original vector (non-op).
   * In Julia, a function may contain multiple concrete implementations (called *methods*), which are selected via multiple dispatch based on the types of all arguments to the call, as compared to functions in Python, which have a single implementation and no polymorphism (as opposed to Python method calls which use a different syntax and allows dispatch on the receiver of the method).
-  * There are no classes in Julia. Instead they are structures (mutable or immutable), containing data but no methods.
+  * There are no classes in Julia. Instead there are structures (mutable or immutable), containing data but no methods.
   * Calling a method of a class instance in Python (`x = MyClass(*args); x.f(y)`) corresponds to a function call in Julia, e.g. `x = MyType(args...); f(x, y)`. In general, multiple dispatch is more flexible and powerful than the Python class system.
   * Julia structures may have exactly one abstract supertype, whereas Python classes can inherit from one or more (abstract or concrete) superclasses.
   * The logical Julia program structure (Packages and Modules) is independent of the file structure (`include` for additional files), whereas the Python code structure is defined by directories (Packages) and files (Modules).