大家进来看看，下面的update语句哪里错了？

str1 = ""
        str1 = "update em_info "
        str1 = str1 + "set c_name='" + c_name.Text + "',"
        str1 = str1 + "bron='" + bron.Text + "',"
        str1 = str1 + "national='" + national.Text + "' "
        str1 = str1 + "where w_name='" + w_name.Text + "'"
        rs2.Open str1, con, 3, 3
        Set rs2 = Nothing错误提示是：update语法错误。
但不知道是哪里错了，请各位指出来。