If conditional marker
you guys subject with supplemental specification
can't form modal + bare infinitive of "form"
a simple phrase direct object (indef. article + adj. + noun)
in preposition of place
a sentence indef. article + noun [in a language with cases, the ending of "sentence" would be determined by whatever the preposition "in" requires]
without what is this?
kind of and this?
arguing deverbal noun (i.e., a noun that comes from a verb)
about it, preposition + pronoun
how adverb
am I supposed verb with inverted word order
to? suffix of a phrasal verb (which is "to be supposed to" as opposed to the nonphrasal "to suppose")

There is a book called something like English Grammar for Dummies. Buy it and read it. It is intended for native speakers.