Hi, i have a simple question

i have a huge list in this form

item number1
item spec1
item number2
item spec2
item number3
item spec3
.
.
.

all i need is converting to this

item number1 item spec1
item number2 item spec2
item number3 item spec3
.
.
.
Transpozing dont work for me, coz list is huge

For any help, i'll be appreciated