His brother has been travelling for a month.
*общий - Has his brother been travelling for a month?
*2 специальных - Where has his brother been travelling for a month?
With whom has his brother been travelling for a month?
*к подлежащему - Who has been travelling for a month?
His brother has been travelling for a month.
*общий - Has his brother been travelling for a month?
*2 специальных - Where has his brother been travelling for a month?
With whom has his brother been travelling for a month?
*к подлежащему - Who has been travelling for a month?