Public Sub Sum()
Dim arr As Variant, k As Integer
'获取最后一行的求和区域的结果
arr = Sheet1.Range("A21:G21").Value
'获取sheet2中最后有内容的下一行的行号
k = Sheet2.Range("A" & Rows.Count).End(xlUp).Row + 1
'将求和结果依次赋值到sheet2中
Sheet2.Range("A" & k).Resize(1, 7).Value = arr
'清除sheet1A2:G20区域内的数值
Sheet1.Range("A2:G20").ClearContents
End Sub