Is it permissible for me to use passive without auxiliary verb?
***** NOT A TEACHER *****
(1) I think that in most cases, the answer is
NO.
(2) The passive is usually defined as a form of "to be" + the past participle:
You can speak English. > English
is spoken by you.
The teachers here treat all members with respect. > All members
are treated with
respect by the teachers here.
You should study your lessons with great diligence. > Your lessons should
be
studied with great diligence (by you).
P.S. In informal English, you may sometimes omit the auxiliary. For example,
if you own a store that sells things to English-speaking tourists, it's fine to put
this sign in the window:
English spoken here. (Instead of "English
is spoken here
by the staff.")