Soldier put inflatable boat in river (7)
I believe the answer is:
draftee
'soldier' is the definition.
(someone drafted into the army)
'inflatable boat in river' is the wordplay.
'inflatable boat' becomes 'raft' (I've seen this in another clue).
'in' indicates putting letters inside.
'river' becomes 'dee' (River Dee).
'raft' going within 'dee' is 'DRAFTEE'.
'put' acts as a link.
(Other definitions for draftee that I've seen before include "one brought into service" , "American military conscript" , "Rookie" , "US conscript" , "One forced to join" .)