English verb conjugation
COULD PRECERTIFY

Regular verb: precertify - precertified - precertified

Affirmation

Simple form	V-ing form
I could precertify you could precertify she could precertify we could precertify you could precertify they could precertify	I could be precertifying you could be precertifying she could be precertifying we could be precertifying you could be precertifying they could be precertifying
Perfect	V-ing perfect
I could have precertified you could have precertified she could have precertified we could have precertified you could have precertified they could have precertified	I could have been precertifying you could have been precertifying she could have been precertifying we could have been precertifying you could have been precertifying they could have been precertifying

Negation

Simple form	V-ing form
I couldn't precertify you couldn't precertify she couldn't precertify we couldn't precertify you couldn't precertify they couldn't precertify	I couldn't be precertifying you couldn't be precertifying she couldn't be precertifying we couldn't be precertifying you couldn't be precertifying they couldn't be precertifying
Perfect	V-ing perfect
I couldn't have precertified you couldn't have precertified she couldn't have precertified we couldn't have precertified you couldn't have precertified they couldn't have precertified	I couldn't have been precertifying you couldn't have been precertifying she couldn't have been precertifying we couldn't have been precertifying you couldn't have been precertifying they couldn't have been precertifying

Interrogative form

Simple form	V-ing form
could I precertify? could you precertify? could she precertify? could we precertify? could you precertify? could they precertify?	could I be precertifying? could you be precertifying? could she be precertifying? could we be precertifying? could you be precertifying? could they be precertifying?
Perfect	V-ing perfect
could I have precertified? could you have precertified? could she have precertified? could we have precertified? could you have precertified? could they have precertified?	could I have been precertifying? could you have been precertifying? could she have been precertifying? could we have been precertifying? could you have been precertifying? could they have been precertifying?

Interro-negative form

Simple form	V-ing form
couldn't I precertify? couldn't you precertify? couldn't she precertify? couldn't we precertify? couldn't you precertify? couldn't they precertify?	couldn't I be precertifying? couldn't you be precertifying? couldn't she be precertifying? couldn't we be precertifying? couldn't you be precertifying? couldn't they be precertifying?
Perfect	V-ing perfect
couldn't I have precertified? couldn't you have precertified? couldn't she have precertified? couldn't we have precertified? couldn't you have precertified? couldn't they have precertified?	couldn't I have been precertifying? couldn't you have been precertifying? couldn't she have been precertifying? couldn't we have been precertifying? couldn't you have been precertifying? couldn't they have been precertifying?