Your sentence
Je+ne+sais+pas+s'il+viendrait
Words in this sentence
ne
not (used alone to negate a verb, now chiefly with only a few particular verbs; see usage notes); not, no (used before a verb, with a coordinating negative element usually following; see usage notes); used in a subordinate clause before a subjunctive verb (especially when the main verb expresses doubt or fear) to provide extra overtones of doubt or uncertainty (but not negating its verb); the so-called "pleonastic" or "expletive" ne; in comparative clauses usually translated with the positive sense of the subsequent negative
Particle
savoir
to know (something); to know how (to do something); to be able to, to be apt to (especially in the negative or interrogative conditional; used in the positive in Belgium); to find out
Verb
pas
The most common adverb of negation in French, typically translating into English as not, don't, doesn't, etc.; used as an intensifier in underlying rhetorical questions, mostly with voilà
Adverb
il
he (third-person singular masculine subject pronoun for human subject); it (third-person singular subject pronoun for grammatically masculine objects); Impersonal subject; it
Pronoun
venir
to come (to move from one place to another that is nearer the speaker); used in venir de with the meaning of "originate from" or "have just done"; to cum, to come, to orgasm
Verb