Regular grammar form

Question

Regular grammar can be of form :-

A->tV or A->Vt or A->t where t is terminal and V is variable.

Here is t string of terminals or a single terminal? I am seeing different definitions of terminal everywhere.

Answer 1

A regular grammar is either right linear or left linear.

Right Linear: If all the productions are of the form
S $\rightarrow$ aA
S $\rightarrow$ a
Where A $\in$ V (set of variable) and a $\in$ $\sum$ *

Left Linear: If all the production are of the form
S $\rightarrow$ Aa
S $\rightarrow$ a
Where A $\in$ V (set of variable) and a $\in$ $\sum$ *.

Note: If we have this kind of production in a grammar then it is neither the right linear nor the left linear. Hence it is not a regular grammar.
S $\rightarrow$ aA
S $\rightarrow$ Aa
S $\rightarrow$ a.
Where A $\in$ V (set of variable) and a $\in$ $\sum$ *.

Comments

I read this definition and according to this definition we can have only a single terminal on RHS of the production right?

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@Xylene  yes at the right side we can have only a single terminal.

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Even I thought the same, but according to this link it seems we can have more than one terminals

http://www.cs.colostate.edu/~massey/Teaching/cs301/RestrictedAccess/Slides/301lecture05.pdf

Please confirm and let me know.

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@Xylene,  yes you are correct. We can have more than one terminals. I verified it from Peter linz. There also they have used more than one terminals at the right side.
Having more than one terminal doesn't effect too much. We can always convert it such that right side is single terminal. For ex:
S $\rightarrow$ abc.
You can convert this like,
S $\rightarrow$ aA
A $\rightarrow$ bB
B $\rightarrow$ c.

But yes definition is the definition and we should follow the definition. So yes we can have more than one terminal at the right side.

Answer 2

proper defination regular grammar will be- 

V -> T*V+T*(right linear grammar)

        or 

V->  VT*+T*(left linear grammmar)