English verb conjugation
COULD TIP

Regular verb: tip - tipped - tipped

Affirmation

Simple form	V-ing form
I could tip you could tip she could tip we could tip you could tip they could tip	I could be tipping you could be tipping she could be tipping we could be tipping you could be tipping they could be tipping
Perfect	V-ing perfect
I could have tipped you could have tipped she could have tipped we could have tipped you could have tipped they could have tipped	I could have been tipping you could have been tipping she could have been tipping we could have been tipping you could have been tipping they could have been tipping

Negation

Simple form	V-ing form
I couldn't tip you couldn't tip she couldn't tip we couldn't tip you couldn't tip they couldn't tip	I couldn't be tipping you couldn't be tipping she couldn't be tipping we couldn't be tipping you couldn't be tipping they couldn't be tipping
Perfect	V-ing perfect
I couldn't have tipped you couldn't have tipped she couldn't have tipped we couldn't have tipped you couldn't have tipped they couldn't have tipped	I couldn't have been tipping you couldn't have been tipping she couldn't have been tipping we couldn't have been tipping you couldn't have been tipping they couldn't have been tipping

Interrogative form

Simple form	V-ing form
could I tip? could you tip? could she tip? could we tip? could you tip? could they tip?	could I be tipping? could you be tipping? could she be tipping? could we be tipping? could you be tipping? could they be tipping?
Perfect	V-ing perfect
could I have tipped? could you have tipped? could she have tipped? could we have tipped? could you have tipped? could they have tipped?	could I have been tipping? could you have been tipping? could she have been tipping? could we have been tipping? could you have been tipping? could they have been tipping?

Interro-negative form

Simple form	V-ing form
couldn't I tip? couldn't you tip? couldn't she tip? couldn't we tip? couldn't you tip? couldn't they tip?	couldn't I be tipping? couldn't you be tipping? couldn't she be tipping? couldn't we be tipping? couldn't you be tipping? couldn't they be tipping?
Perfect	V-ing perfect
couldn't I have tipped? couldn't you have tipped? couldn't she have tipped? couldn't we have tipped? couldn't you have tipped? couldn't they have tipped?	couldn't I have been tipping? couldn't you have been tipping? couldn't she have been tipping? couldn't we have been tipping? couldn't you have been tipping? couldn't they have been tipping?