Be the first to explore employing one taking drugs in Puerto Rico (7)
I believe the answer is:
pioneer
'be the first to explore' is the definition.
I can't tell whether this definition defines the answer.
'one taking drugs in puerto rico' is the wordplay.
'one' becomes 'i' (roman numeral).
'taking' becomes 'on' (eg one taking drugs is 'on' drugs).
'drugs' becomes 'ee' (I've seen this in other clues).
'in' means one lot of letters goes inside another.
'puerto rico' becomes 'pr' (abbreviation for Puerto Rico).
'i'+'on'+'ee'='ionee'
'ionee' going into 'pr' is 'PIONEER'.
'employing' acts as a link.
Can you help me to learn more?
(Other definitions for pioneer that I've seen before include "Colonist" , "Innovate" , "spacecraft" , "Founder" , "Open up an area" .)