IT device penned verse in 2000 (5)
I believe the answer is:
modem
'it device penned' is the definition.
The definition suggests a singular noun which matches the answer.
'verse in 2000' is the wordplay.
'verse' becomes 'ode' (ode is a type of poem or verse).
'in' means one lot of letters goes inside another.
'2000' becomes 'MM' (2000 in Roman numerals).
'ode' going within 'mm' is 'MODEM'.
Can you help me to learn more?
(Other definitions for modem that I've seen before include "Device used with computer" , "Device connecting computer to telephone system" , "Phone line and computer connector" , "(Wireless) communication device" , "Device for connecting two computers" .)