Il y a deux mois qu'il est parti.

1.   ?    He left for two months.
2.   ?    He has been away since two months.
3.   ?    He has been going away for two months.
4.   ?    He has been away for two months.

Elles font du shopping depuis que je les ai amenées en ville, ce matin.

1.   ?    They have been shopping since I have been driving them to town this morning.
2.   ?    They are shopping since I drove them to town this morning.
3.   ?    They have been shopping since I drove them to town this morning.
4.   ?    They have been shopping for the time I drove them to town this morning.

Il a été nommé directeur il y a deux ans et il y a deux mois qu'elle le connaît.

1.   ?    He has been appointed manager for two years and has known her for two months.
2.   ?    He was appointed manager two years ago and has been knowing her for two months.
3.   ?    He was appointed manager two years ago and has known her two months ago.
4.   ?    He was appointed manager two years ago and has known her for two months.