How to create array of dynamic sized string arrays in C++

#include <iostream>
#include <vector>
#include <sstream>
using namespace std;

int main()
{
  const std::string input = "Hello. My name is A.\nI am from B.\n";

  vector <vector < string > > vline;

  while ( true )
  {
    string line;
    getline(cin, line);
    if ( ! cin ) break;
    vector <string> vword;
    istringstream iss ( line );
    while ( true )
    {
      string word;
      iss >> word;
      if ( ! iss ) break;
      vword.push_back( word );
    }
    vline.push_back( vword );
  }

  cout << "{\n";
  for (const auto & vw : vline)
  {
    cout << "{";
    for ( const auto & w  : vw )
    {
      cout << "\"" << w << "\", ";
    }
    cout << "},\n";

  }
  cout << "}\n";
}

Hello. My name is A.
I am from B.

{
{"Hello.", "My", "name", "is", "A.", },
{"I", "am", "from", "B.", },
}