Sub test()
Dim c, z, y As String
c = "toto tati tutu"
z = InStr(c, " ")
x = Application.Proper(Left(c, z)) ' la première lettre du premier mot
'x=Ucase((Left(c, z)) ' le premier mot en majuscule
y = Len(x)
z = Right(c, Len(c) - y)
MsgBox x & z
End Sub