1. Tony smart.
2. Mira in the classroom right now.
3. David a doctor.
Those expressions is understandable, however, grammatically, those expressions miss of auxiliary words. They miss the word "is". So the proper grammar for those expressions are:
1. Tony is smart.
2. Mira is in the classroom right now.
3. David is a doctor.
How is that?
Well, besides "is", there is a bunch of auxiliary words exist in the English speaking society, such as;
- are
- is
- was
- were
- will
- shall
- have
- may
- can
- could
- should
- have
- has
- would
- had
- been
- may
- must
The usage of each auxiliary words can be found completely in the following link.