English -- and most familiar languages -- have a variety of subordinate clauses, chunks of language that are almost sentences but cannot stand on their own as fully meaningful. toki pona has no such chunks of language, everything that is like a sentence is a sentence. And yet, subordinate clauses play several important roles in English and these roles need to be played in toki pona as well. This paper is about how toki pona covers these roles. Most of it is familiar; on the context and bringing them all together is added.
The easiest -- and most familiar -- case is indirect discourse. This presents the gist of what someone said (or thought or wrote or . ) without actually quoting it verbatim. In English, it typically involves a clause that begins with "that" (apparently a special one, just for this purpose). and involves several shifts of reference, in pronouns and times, especially. If someone actually says "I will be there tomorrow", this may be reported as "He said that he would be here (or at the place) today (or on the Snext day)" where the variations depend on when and where the report is made (Sorting out the time shifts are a large part of the gramar of many familiar languages, the "sequence of tense" and the various forms that this requires.) . In toki pona, the same move is made using the ordinary 'ni "that"', a deictic pronoun pointing to the following sentence, which is just the sentential part of the English version, complete with referential shifts as needed (but not usually tense, of course). ona li toki e nimi 'tenpo suno kama la mi lon ni' become 'ona li toki e ni: tenpo suno ni la ona li lon ni' (or as required).
Almost equally straightforward are cases of non-restrictive relative clauses, which add new -- but relatively less salient -- information about someone already identified. These are marked by the occurrence of a relative pronoun (who, what, which, that, . ) in place of some significant noun in what would otherwise be a sentence. Usage -- and especially "good usage', e.g., in style books -- varies all over the place on these, depending on country and year and tone and what have you. Apparently, the current "best" American usage is to set such clauses off with commas and to use the wh pronouns. "John, who has a dog, is going to Italy", where it is the trip that is the focus and the dog just enters in as interesting side information. In toki pona, the corresponding structure is just two consecutive sentences, the less central one second, with a pronominal phrase adequate to insure identification: 'jan Jon li tawa ma Italija. ona (mije/ jan ni) li jo e soweli tomo.'
Mention of non-restrictive relative clauses raises immediately the issue of restrictive relative clauses. These function to further identify a vaguely specified object which then plays a role in the main line of the text. In English, these are again marked with wh relative pronouns (which look just like interrogative ones) or 'that". Current fashion seems to be to prefer "that" as the connector and to not use commas to set the clause off: "The man that came to dinner stayed a month" (in was "the man who came" when the play was written in the 1930s). In toki pona the pattern is to use two sentences and always use 'ni' somewhere. Generally, the sentence corresponding to the relative clause is first and the main clause is second, with the 'ni' occurring at the appropriate place in the second sentence. But there is some variations on both which sentence comes first and where the 'ni' goes. The proposed pattern seems clearest (to me, today): 'jan li kama. tawa moku. jan ni li awen. lon tenpo mun.'
Somewhat more remote from ordinary full sentences (and so, sometimes not considered clauses at all) are expressions where the verb is an infinitive (introduced by a special "to") and the subject, if present at all is either in the direct object form (when detectable) or introduced by "for" or the like. These are generally associated with intentional verbs (wanting, intending and the like) and related prepositions ("in order", 'because", . ). "She wanted him to go" ("She wanted for him to go" in some cases, "She wanted to go herself" when she is also the subordinate subject) . The tp solution is again 'ni' in the appropriate object slot (for the verb or preposition) and the subordinate sentence as that indicated by the deixis: 'ona meli li wile e ni: ona mije li tawa' ('ona li wile e ni: ona li tawa' collapses as 'ona li wile tawa' as English does to "She wanted to go"). [Although the tp sentences are grammatically separate, a semantic/pragmatic/logic subordination persists, to prevent the word from being populated by wished-for horses. If 'mi jo e soweli tawa' is true, then so is 'soweli tawa li lon' but if 'mi wile e (ni: mi jo e) soweli tawa' 'soweli tawa li lon' does not follow.]
There are probably more cases to consider, but these are the main ones. Please call my attention to further cases.