In a certain code language, 'NAILS' is written as 'PYGNU', and 'TEXT' is written as 'VCZV. How will 'FOREST' be written in that language?

HMTCUV

1   2    3    4   5    6   7     8    9  10  11  12  13

 A   B   C    D   E    F   G    H    I    J    K    L   M

 ↓    ↓    ↓    ↓    ↓     ↓   ↓    ↓     ↓   ↓    ↓    ↓    ↓

 Z   Y    X   W   V    U   T    S    R   Q   P    O   N

26  25  24  23  22  21  20  19  18  17  16  15  14

The logic here is;

(subtraction of -2 in vowels)

(addition +2 in consonant)

So,

 'NAILS' is written as 'PYGNU', 

N +2  P

A -2  Y

I -2  G

L +2  N

S +2  U

And,

T +2  V

E -2  C

X +2  Z

T +2  V

Similarly,

F +2  H

O -2  M

R +2  T

E -2  C

S +2  U

T +2  V

Thus, HMTCUV is correct.