The pattern of given letter series is :-
a b b n
After completing the pattern, we will get complete letter series.
a b b n/ a bb n/ a bb n/ abbn

As per given question, the letter series is following the below pattern.
b c b
After completing the pattern, we will get complete letter series.
b c b / a c a / b c b / a c a / b cb / a c a / b

The pattern of given letter series is :-
a abaa c
Using the same pattern, we will get complete letter series.
a abaa c/aaba c c/a a b

The given letter series in below pattern.
cab d
After using the pattern the complete letter series will be as below.
cab d/ c a bd/ ca b d/ c abd

As per given question, the letter series is following the below pattern.
a b b b ba
After using the pattern the complete letter series will be as below.
a b b b ba / a b bb ba

As per given question, the letter series is following the below pattern.
d m n m
Using the same pattern, we will get complete letter series.
d m n m/ dm nn / dm n n

As per given question, the letter series is following the below pattern.
a b b a
Using the same pattern, we will get complete letter series.
a b b a / a bb a a b b a

The given letter series in below pattern.
p q r
Using the same pattern, we will get complete letter series.
p q r / p q r / pqr / p q r

The pattern of given letter series is :-
a bcc b a
After using the pattern the complete letter series will be as below.
a bcc b a / abc c ba / ab c

The given letter series in below pattern.
b d f g g
After completing the pattern, we will get complete letter series.
b d f g g / b d f g g