I could signalise you could signalise he could signalise we could signalise you could signalise they could signalise
V-ing form
I could be signalising you could be signalising he could be signalising we could be signalising you could be signalising they could be signalising
Perfect
I could have signalised you could have signalised he could have signalised we could have signalised you could have signalised they could have signalised
V-ing perfect
I could have been signalising you could have been signalising he could have been signalising we could have been signalising you could have been signalising they could have been signalising
Negation
Simple form
I couldn't signalise you couldn't signalise he couldn't signalise we couldn't signalise you couldn't signalise they couldn't signalise
V-ing form
I couldn't be signalising you couldn't be signalising he couldn't be signalising we couldn't be signalising you couldn't be signalising they couldn't be signalising
Perfect
I couldn't have signalised you couldn't have signalised he couldn't have signalised we couldn't have signalised you couldn't have signalised they couldn't have signalised
V-ing perfect
I couldn't have been signalising you couldn't have been signalising he couldn't have been signalising we couldn't have been signalising you couldn't have been signalising they couldn't have been signalising
Interrogative form
Simple form
could I signalise? could you signalise? could he signalise? could we signalise? could you signalise? could they signalise?
V-ing form
could I be signalising? could you be signalising? could he be signalising? could we be signalising? could you be signalising? could they be signalising?
Perfect
could I have signalised? could you have signalised? could he have signalised? could we have signalised? could you have signalised? could they have signalised?
V-ing perfect
could I have been signalising? could you have been signalising? could he have been signalising? could we have been signalising? could you have been signalising? could they have been signalising?
Interro-negative form
Simple form
couldn't I signalise? couldn't you signalise? couldn't he signalise? couldn't we signalise? couldn't you signalise? couldn't they signalise?
V-ing form
couldn't I be signalising? couldn't you be signalising? couldn't he be signalising? couldn't we be signalising? couldn't you be signalising? couldn't they be signalising?
Perfect
couldn't I have signalised? couldn't you have signalised? couldn't he have signalised? couldn't we have signalised? couldn't you have signalised? couldn't they have signalised?
V-ing perfect
couldn't I have been signalising? couldn't you have been signalising? couldn't he have been signalising? couldn't we have been signalising? couldn't you have been signalising? couldn't they have been signalising?