Update reference-types.rst

Clarify comment using language similar to that in the Array section of the documentation. Previously it said simply "Because of that..." but what the word "that" was about, was not evident.

docs/types/reference-types.rst

@@ -379,8 +379,10 @@ Array Members
         uint[2**20] aLotOfIntegers;
         // Note that the following is not a pair of dynamic arrays but a
         // dynamic array of pairs (i.e. of fixed size arrays of length two).
-        // Because of that, T[] is always a dynamic array of T, even if T
-        // itself is an array.
+        // In Solidity, T[k] and T[] are always arrays with elements of type T,
+        // even if T itself is an array.
+        // Because of that, bool[2][] is a dynamic array of elements
+        // that are bool[2]. This is different from other languages, like C.
         // Data location for all state variables is storage.
         bool[2][] pairsOfFlags;