1. Meanings of the voices
active:
The subject acts.
passive:
The subject receives the action.
middle:
The subject is indirectly affected by the action.

2. What is a defective verb?
It is a verb with the form of middle voice but the meaning of active voice.
What is the meaning of the aorist tense?
The aorist tense sees the action in its totality.

3. Meanings of the moods
Indicative
Indicates something.
Subjuntive
Shows probability, purpose, emotion contrary to reality
Imperative
Command
Infinitive
Unlimited (Used grammatically as a noun.)
Participle
Similar to a participle in English
(Verb used grammatically as an adjective.)