VBA dictionary concept problem

[straw]

Hi all, I am following some sites to learn vba dictionary right now. However, some codes I can't understand. Please help to explain. Really appreciate your help.

Questions are inside "" after the code.

Please see codes below.

Sub ProcessData1()
Dim dict As Dictionary
Dim i As Integer
Dim targetRow As Integer
Dim name As String
Dim subject As String
Dim score As Double
Dim more As Boolean
Set dict = New Dictionary
more = True
i = 2
Worksheets("English").UsedRange.Clear
Worksheets("Physics").UsedRange.Clear
Worksheets("Biology").UsedRange.Clear
While more
name = Worksheets("Data").Cells(i, 1).Value
    subject = Worksheets("Data").Cells(i, 3).Value
    score = Worksheets("Data").Cells(i, 4).Value
If dict.Exists(subject) Then
        targetRow = dict.Item(subject)      "At this time, dict.item(subject)=score or name, or both?"
    Else
        targetRow = 1                "Why does targetRow=1 here?"
    End If
Worksheets(subject).Cells(targetRow, 1) = name
    Worksheets(subject).Cells(targetRow, 2) = score
    dict.Item(subject) = targetRow + 1     
i = i + 1
If Len(Worksheets("Data").Cells(i, 1)) = 0 Then more = False    "Does this code mean that go until the last filled row?"
Wend
End Sub

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