Some Notes and Practice Problems on Syntactic Tree Structures
1. Some Notes on Drawing Syntactic Trees
In any ‘Introduction to Linguistics’ course, there comes a time when you are asked to use Phrase
Structure (PS) rules to draw syntactic trees for various sentences of English. In this class, our PS
rules for English currently look as follows:
(1) Our Current PS Rules for English
S { NP , CP } VP
NP (D) (A*) N (CP) (PP*)
VP V (NP) { (NP) , (CP) } (PP*)
PP P (NP)
CP C S
But how, exactly, do we use these PS rules to draw syntactic trees for sentences of English?
Now, the bad news is that finding the right tree-structure for a sentence always requires a
modicum of insight and ingenuity. However, there is a way of proceeding through the problem
that makes the answer easier to see.
To see this, let’s work step-by-step through a particular complex example:
(2) Illustrative Sentence The good boy in the class built Tom a new wooden table.
So, how do we figure out the tree structure for this sentence? We start off as follows:
(3) First Step: Label the Words in the Sentence
Above each word in the sentence, write the category label for that word and attach it with
a line.
Applying this first step to our illustrative sentence, we get the following:
(4) Applying the First Step to Sentence (2)
D A N P D N V N D A A N
The good boy in the class built Tom a new wooden table.
Now, having drawn the category label for each word, the name of the game is to find
rules from the list of PS rules that can combine those category labels into larger phrases. The
way to proceed here is completely open-ended, but one strategy I find useful is to start off by
trying to form the NPs in the sentence.
(5) Second Step: Try to Form NPs
From the list of category labels created in Step 1, group Ns together with other categories
to create NPs (following the PS rule for NPs that we have).
• Look to each N in the sentence.
• Draw an NP label above the N, and connect it to the N with a line.
• If the N is directly preceded by a D, connect it to the NP label
• If the N is directly preceded by a sequence of As, connect each A to the NP label
o If there is also a D before the As, connect that to the NP label as well.
Applying Step 2 to the structure we made in (4) will result in the following:
(6) Applying the Second Step to Sentence (2)
NP NP NP NP
D A N P D N V N D A A N
The good boy in the class built Tom a new wooden table.
Next, I personally find it easy to form the PPs in the sentence. To do so, we follow the
procedure laid out in (7).
(7) Third Step: Try to Form PPs
If there are any Ps, group the Ps together with any following NPs into a PP.
• Look to each P in the sentence.
• Draw a PP label above the P, and connect it to the P with a line.
• If the P is followed by an NP (created in Step 2), connect that NP to the PP label.
Applying Step 3 to the structure we made in (6) will result in the following:
(8) Applying the Third Step to Sentence (2)
PP
NP NP NP NP
D A N P D N V N D A A N
The good boy in the class built Tom a new wooden table.
Now, I should note here that this third step in (7) is not ‘foolproof’. It may sometimes be that a P
is followed by NP but the NP is not really part of a PP. For example, we see this in sentences like
the one in (9) below.
(9) A Sentence Where Step Three Will Lead You Astray
In the sentence below, the NP a coat follows the P outside, but is not part of a PP.
S
NP VP
N V NP NP
Dave gave D N PP D N
the boy P a coat
outside
In cases like this, if you see that applying Step 3 will give the wrong result, you have to choose
not to apply it. I wish I could give you a foolproof way of figuring out whether to use Step 3 or
not, but it’s really not possible. This is something that you’ll have to work out through good old-
fashioned trial-and-error.
After forming the PPs, I myself find it natural to try to form the VPs in the sentence. To
do so, we follow the procedure laid out in (10).
(10) Fourth Step: Try to Form VPs
Group the Vs together with material following them into a VP.
• Look to each V in the sentence.
• Draw a VP label above the V, and connect to the V with a line.
• If there are phrases following the V that can be part of the VP (according to the rule
in (1)) connect them to the VP label with a line.
Applying Step 4 to the structure we made in (8) will result in the following:
(11) Applying the Fourth Step to Sentence (2)
According to the rules in (1), a VP can be formed form a V followed by two NPs:
VP
PP
NP NP NP NP
D A N P D N V N D A A N
The good boy in the class built Tom a new wooden table.
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