could machine
Verbo regular: machine - machined- machined

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could machine
you could machine
she could machine
we could machine
you could machine
they could machine 	I could be machining
you could be machining
she could be machining
we could be machining
you could be machining
they could be machining	I could have machined
you could have machined
she could have machined
we could have machined
you could have machined
they could have machined	I could have been machining
you could have been machining
she could have been machining
we could have been machining
you could have been machining
they could have been machining	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't machine
you couldn't machine
she couldn't machine
we couldn't machine
you couldn't machine
they couldn't machine 	I couldn't be machining
you couldn't be machining
she couldn't be machining
we couldn't be machining
you couldn't be machining
they couldn't be machining	I couldn't have machined
you couldn't have machined
she couldn't have machined
we couldn't have machined
you couldn't have machined
they couldn't have machined	I couldn't have been machining
you couldn't have been machining
she couldn't have been machining
we couldn't have been machining
you couldn't have been machining
they couldn't have been machining	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I machine?
could you machine?
could she machine?
could we machine?
could you machine?
could they machine? 	could I be machining?
could you be machining?
could she be machining?
could we be machining?
could you be machining?
could they be machining? 	could I have machined?
could you have machined?
could she have machined?
could we have machined?
could you have machined?
could they have machined? 	could I have been machining?
could you have been machining?
could she have been machining?
could we have been machining?
could you have been machining?
could they have been machining? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I machine?
couldn't you machine?
couldn't she machine?
couldn't we machine?
couldn't you machine?
couldn't they machine? 	couldn't I be machining?
couldn't you be machining?
couldn't she be machining?
couldn't we be machining?
couldn't you be machining?
couldn't they be machining? 	couldn't I have machined?
couldn't you have machined?
couldn't she have machined?
couldn't we have machined?
couldn't you have machined?
couldn't they have machined? 	couldn't I have been machining?
couldn't you have been machining?
couldn't she have been machining?
couldn't we have been machining?
couldn't you have been machining?
couldn't they have been machining?