error: ‘list’ is not a member of ‘std’

I'm trying to compile my header file, but I'm getting errors I can't figure out.

I want to create a struct that contains 3 maps: -map from single words to counts -map from word pairs to counts -map from single words to list of following words

The code in my header file:

#include <cstdlib>    
#include <iostream>    
#include <cstring>    
#include <string>    
#include <cctype>    
#include <vector>    
#include <algorithm>    
#include <map>   


    typedef struct {

    std::map<std::string, int> firstCounts;

    std::map<std::string, int> pairCounts;

    std::map<std::string, std::list<std::string>> follows; //You can use an iterator to retrieve the values stored in the list. 

    } LanguageModel;

And the errors I'm getting:

LangModel.h:24:23: error: ‘list’ is not a member of ‘std’
 std::map<std::string, std::list<std::string>> follows; //You can use an iterator to retrieve the values stored in the list. 
                       ^
LangModel.h:24:23: error: ‘list’ is not a member of ‘std’
LangModel.h:24:38: error: template argument 2 is invalid
 std::map<std::string, std::list<std::string>> follows; //You can use an iterator to retrieve the values stored in the list. 
                                      ^
LangModel.h:24:38: error: template argument 4 is invalid
LangModel.h:24:44: error: expected unqualified-id before ‘>’ token
 std::map<std::string, std::list<std::string>> follows; //You can use an iterator to retrieve the values stored in the list.