一小段关键词分析代码(VB)

帮朋友改的一小段关键词分析代码； 含两个单词复合计数
Private Function CollectWords() As Dictionary(Of String, Integer)
'Create a new dictionary
Dim table As New Dictionary(Of String, Integer)
'Prompt for the user
Console.WriteLine(
"Enter a line : ")
'Get the user's input
Dim input As String = Console.ReadLine()
'Split the line and make an array of words
Dim words As String() = input.Split()
Dim wordPrev As String = ""
'Search the array
For Each word In words
'We can get the lowercase, not necessary here
Dim wordKey As String = word.ToLower()
'If the dictionay contains the words
If table.ContainsKey(wordKey) Then
'increment
table(wordKey) = table(wordKey) + 1
Else
'add a new word with a count of 1 in the dictionary
table.Add(wordKey, 1)
End If
Dim wordKey2 As String = (wordPrev + " " + word).ToLower()
If wordPrev <> "" Then
If table.ContainsKey(wordKey2) Then
'increment
table(wordKey2) = table(wordKey2) + 1
Else
'add a new word with a count of 1 in the dictionary
table.Add(wordKey2, 1)
End If
End If
wordPrev = word
Next
Return table
End Function