the words in bold are o-ordinations (another in English is or), used to conjoin (=join together) strings of simple sentences. technically, example (19) does illustrate a complex sentence, since it's a sentence containing more than one clause. however, all the clauses. there are on syntactic restriction on their order, although there may be pragmatic restrictions (the sentence may not make good sense). linguists tend to reserve the term 'complex sentence' for examples such as (20). these have one main clause (underlined) and at least one subordinate clause