could thunder
Verbo regular: thunder - thundered- thundered

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
-
-
it could thunder
-
-
- 	-
-
it could be thundering
-
-
- 	-
-
it could have thundered
-
-
- 	-
-
it could have been thundering
-
-
- 	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
-
-
it could not thunder
-
-
- 	-
-
it could not be thundering
-
-
- 	-
-
it could not have thundered
-
-
- 	-
-
it could not have been thundering
-
-
- 	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
-
-
could it thunder?
-
-
- 	-
-
could it be thundering?
-
-
- 	-
-
could it have thundered?
-
-
- 	-
-
could it have been thundering?
-
-
- 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
-
-
could it not thunder?
-
-
- 	-
-
could it not be thundering?
-
-
- 	-
-
could it not have thundered?
-
-
- 	-
-
could it not have been thundering?
-
-
-