Generally, you don't.

IMPLODE and EXPLODE were functions in old lisps where there was no string data type, so that symbols were the only way of manipulating text. Then (explode 'foo) would give you (F O O); you could then do (implode (cdr (explode 'crash))) to give you back the symbol RASH

If you are taught today about implode/explode in a lisp programming class for anything other than historical context, complain loudly to your lecturer.

If arrays and structures don't exist, then obviously MAKE-ARRAY and DEFSTRUCT must be figments of the imagination. Similarly, since Lisp only uses association lists to organize "database-like" information, MAKE-HASH-TABLE must also be a figment of the imagination.

Based on the nonexistence of the above figments of the imagination, Perl and Python, with arrays, associative tables, and dictionaries, must obviously be manifestly superior.