Dear jeyagowri,
If the tables to be exported are stored in SYSTEM tablespace in Source DB and if you import them in Targed db, these tables will be stored in the SYSTEM tablespace of the target DB, no matter which tablespace the target DB user is assigned to.
If you want to move tables to Users default tablespace or whereever you want, You can use ALTER TABLE...MOVE command to perform these task.
Thanks,
Hings
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