The second is related to the active clause "I could not draw this picture." Neither of the passive versions is particularly idiomatic, though.
– Dec 24 '13 at 15:23
possible duplicate of [What is difference between "Can", "Could", "Will", "Would", "Shall", and "Should"?](http://ell.stackexchange.com/questions/5251/what-is-difference-between-can-could-will-would-shall-and-should)
– ЯegDwightDec 24 '13 at 15:23
I noticed in some grammar site that in active/passive voice conversion,modals are not changing.Hence I think first option seems to be correct.
– ArunDec 24 '13 at 16:11
The difference is the same as the difference between: "I am not able to draw the picture" and "I was not able to draw the picture"
– JimDec 24 '13 at 16:31
1 Answers1
2
The passive voice does not change the tense. Therefore, option 1 is correct.