>>66
じゃあこんな感じ

Sub test()
n = ActiveSheet.Cells(Rows.Count, 1).End(xlUp).Row
Cells.Interior.ColorIndex = 0

For i = 1 To n
If Worksheets("休日").Cells(i, 2) <> "" Then
Range("a" & i+8 & ":n" & i+8).Interior.Color = RGB(192, 192, 192)
End If
Next

End Sub