I can fertilise you can fertilise he can fertilise we can fertilise you can fertilise they can fertilise
V-ing form
I can be fertilising you can be fertilising he can be fertilising we can be fertilising you can be fertilising they can be fertilising
Perfect
I can have fertilised you can have fertilised he can have fertilised we can have fertilised you can have fertilised they can have fertilised
V-ing perfect
I can have been fertilising you can have been fertilising he can have been fertilising we can have been fertilising you can have been fertilising they can have been fertilising
Negation
Simple form
I can't fertilise you can't fertilise he can't fertilise we can't fertilise you can't fertilise they can't fertilise
V-ing form
I can't be fertilising you can't be fertilising he can't be fertilising we can't be fertilising you can't be fertilising they can't be fertilising
Perfect
I can't have fertilised you can't have fertilised he can't have fertilised we can't have fertilised you can't have fertilised they can't have fertilised
V-ing perfect
I can't have been fertilising you can't have been fertilising he can't have been fertilising we can't have been fertilising you can't have been fertilising they can't have been fertilising
Interrogative form
Simple form
can I fertilise? can you fertilise? can he fertilise? can we fertilise? can you fertilise? can they fertilise?
V-ing form
can I be fertilising? can you be fertilising? can he be fertilising? can we be fertilising? can you be fertilising? can they be fertilising?
Perfect
can I have fertilised? can you have fertilised? can he have fertilised? can we have fertilised? can you have fertilised? can they have fertilised?
V-ing perfect
can I have been fertilising? can you have been fertilising? can he have been fertilising? can we have been fertilising? can you have been fertilising? can they have been fertilising?
Interro-negative form
Simple form
can't I fertilise? can't you fertilise? can't he fertilise? can't we fertilise? can't you fertilise? can't they fertilise?
V-ing form
can't I be fertilising? can't you be fertilising? can't he be fertilising? can't we be fertilising? can't you be fertilising? can't they be fertilising?
Perfect
can't I have fertilised? can't you have fertilised? can't he have fertilised? can't we have fertilised? can't you have fertilised? can't they have fertilised?
V-ing perfect
can't I have been fertilising? can't you have been fertilising? can't he have been fertilising? can't we have been fertilising? can't you have been fertilising? can't they have been fertilising?