Some parts of the analysis are very different from 'real' syntax, but it provokes thinking about why certain facts are the way they are and what the explanation might be for that. We also try to get the students to see that they can do scientific tests to find stuff out, and that the data should be their guide.
Anyway, the students find it quite hard, but over time they become skilled at identifying adverbials, complements, subjects, noun phrases, possessive determiners and whatnot. They'll sit their exam next week and most of them will pass, and some will excel.
But one thing that they find particularly hard, I've found, is what we call ACAs, or Abbreviated Clausal Analyses. This means that they have to analyse complex sentences with two, three or even four clauses, but they don't have to draw a full tree, only an abbreviated one (using triangles to represent the clauses).
Today, I ran a 'syntax surgery' and we spent ages doing these. One that was especially problematic was this one:
He suggested that the recipe should remain a secret until all the food had been eaten.
We have three clauses here, each headed by a verb: suggested, remain, and eaten. The trick is to find the clauses, and then to say what the function of each is. Here's the sentence bracketed into clauses:
[S1 He suggested [S2 that the recipe should remain a secret until [S3 all the food had been eaten]]]The problem we had was with that until. They thought, and actually I agree with them, that until should be in S3. However, the analysis in the book is that because until could also take an NP complement, it must still be a preposition heading a PP. This is a bit hard to grasp, but once convinced of it, they argued that the PP crosses two clauses (I was so pleased that they thought this was a problem, because at the start of the semester they have no sense that that's bad). It doesn't, though, because the whole PP until all the food had been eaten is within S2, and only indirectly within S1. That PP has within it a clausal complement. This is a concept that they've seen before, many times, but the fact that it's a clause just adds that extra difficulty.
Still, hopefully they'll keep their heads and perform brilliantly in their exam.