Can

Helping Verb Can

Active Formula:
S + Can + V1 + O
Eg: I can swim in the river
Eg: He can drive the big car.
Eg: Ramesh can sing the song.

Question:
Can + S + V1 + O ?
Eg: Can i write a letter?
Eg: Can he sing a song?
Eg: Can we fight for our rights?

Passive Formula:
O + Can + Be + V3 + (by s)
Eg: Letter can be written.

Question:
Can + O + Be + V3 + (by s)
Eg: Can letter be written by you?
Eg: Can children be fed?