I can sneeze you can sneeze he can sneeze we can sneeze you can sneeze they can sneeze
V-ing form
I can be sneezing you can be sneezing he can be sneezing we can be sneezing you can be sneezing they can be sneezing
Perfect
I can have sneezed you can have sneezed he can have sneezed we can have sneezed you can have sneezed they can have sneezed
V-ing perfect
I can have been sneezing you can have been sneezing he can have been sneezing we can have been sneezing you can have been sneezing they can have been sneezing
Negation
Simple form
I cannot sneeze you cannot sneeze he cannot sneeze we cannot sneeze you cannot sneeze they cannot sneeze
V-ing form
I cannot be sneezing you cannot be sneezing he cannot be sneezing we cannot be sneezing you cannot be sneezing they cannot be sneezing
Perfect
I cannot have sneezed you cannot have sneezed he cannot have sneezed we cannot have sneezed you cannot have sneezed they cannot have sneezed
V-ing perfect
I cannot have been sneezing you cannot have been sneezing he cannot have been sneezing we cannot have been sneezing you cannot have been sneezing they cannot have been sneezing
Interrogative form
Simple form
can I sneeze? can you sneeze? can he sneeze? can we sneeze? can you sneeze? can they sneeze?
V-ing form
can I be sneezing? can you be sneezing? can he be sneezing? can we be sneezing? can you be sneezing? can they be sneezing?
Perfect
can I have sneezed? can you have sneezed? can he have sneezed? can we have sneezed? can you have sneezed? can they have sneezed?
V-ing perfect
can I have been sneezing? can you have been sneezing? can he have been sneezing? can we have been sneezing? can you have been sneezing? can they have been sneezing?
Interro-negative form
Simple form
can I not sneeze? can you not sneeze? can he not sneeze? can we not sneeze? can you not sneeze? can they not sneeze?
V-ing form
can I not be sneezing? can you not be sneezing? can he not be sneezing? can we not be sneezing? can you not be sneezing? can they not be sneezing?
Perfect
can I not have sneezed? can you not have sneezed? can he not have sneezed? can we not have sneezed? can you not have sneezed? can they not have sneezed?
V-ing perfect
can I not have been sneezing? can you not have been sneezing? can he not have been sneezing? can we not have been sneezing? can you not have been sneezing? can they not have been sneezing?