Dim gradeNum As Long

Sub WhatGrade()
    gradeNum = InputBox("Type a grade from 0 to 100")
    NestedIf
End Sub

Sub NestedIf()
If gradeNum > 90 Then
MsgBox ("Great job. You got an A.")
If gradeNum = 100 Then
MsgBox ("You are perfect.")
End If
ElseIf gradeNum > 80 Then
MsgBox ("Good work. B is a very good grade.")
ElseIf gradeNum > 70 Then
MsgBox ("Not bad. C is still passing.")
If gradeNum < 72 Then
MsgBox ("That was close. You were lucky to get a C.")
End If
Else
MsgBox ("You can do better than this.")
End If
If gradNum > 70 Then
MsgBox ("You have passed this class.")
End If
End Sub