The Core Concept
A participial phrase is a descriptive phrase that starts with a verb ending in -ing (present participle) or -ed/-en (past participle). On the SAT, these phrases do not act as main verbs. Instead, they act as giant adjectives describing a noun.
The SAT tests these phrases in two distinct positions. You must learn how to diagram both.
The 2 Structural Positions (And How to Diagram Them)
Position 1: The Introductory Modifier
The phrase comes at the very beginning of the sentence to set up the main clause. [1]
📐 The Diagram Workflow
[ Modifier Phrase starting with -ing / -ed ] , [ TARGET NOUN ]
│ ▲
└─────────────── (Draw Arrow Forward) ─────────┘- Find the Anchor: Locate the
ingoredmodifier at the start. - Draw the Arrow: Draw a mental arrow forward to the noun immediately following the comma.
- The Logic Check: Ask yourself: Is this noun physically performing the action of the modifier?
- ❌ Wrong: Swimming near the surface, the tourists photographed the orca. (Arrow points to tourists. This implies the tourists were swimming in the open ocean).
- Correct: Swimming near the surface, the orca was photographed by tourists. (Arrow points to orca. This is logical).
Position 2: The Trailing Modifier
The sentence starts with a complete independent clause, and the modifier is tacked onto the end after a comma. [1]
📐 The Diagram Workflow
[ TARGET NOUN ] ... [ Rest of Clause ] , [ Modifier Phrase starting with -ing ]
▲ │
└─────────────── (Draw Arrow Backward) ───┘- Find the Anchor: Locate the
ingmodifier after the comma at the end of the sentence. - Draw the Arrow: Draw a mental arrow backward to find the main subject or the overall action of the preceding clause.
- The Logic Check: Ask yourself: Did the main subject cause or perform this trailing action as a direct result of the main verb?
- ❌ Wrong (Comma Splice): The biologists tracked the pod, they recorded its behavior. (Two independent clauses joined by a comma).
- Correct: The biologists tracked the pod, recording its behavior. (Arrow points back to biologists / tracked. "Recording" tells us what the biologists did as a direct result of tracking).
Interactive SAT Practice
Test your skills on these 5 SAT-style multiple-choice questions applying both positions.
Question 1 (Position 1: Introductory Modifier)
Having finished her research paper, ________. Which choice best completes the sentence?
- A) the printer suddenly ran out of ink.
- B) a well-deserved vacation was finally on her mind.
- C) Maria submitted it to her professor before the deadline.
- D) the deadline was easily met by the student.
Answer: C
- Diagram Action: Draw arrow forward from "Having finished" to the noun after the comma.
- Reason: Maria is the only noun capable of physically finishing a research paper. Options A, B, and D create dangling modifiers because a printer, a vacation, and a deadline cannot write papers.
Question 2 (Position 2: Trailing Modifier)
The team celebrated their historic victory until midnight, ________ loudly into the night. Which choice best completes the sentence?
- A) they cheered
- B) cheering
- C) and cheered
- D) having cheered
Answer: B
- Diagram Action: Draw arrow backward from the blank to the main subject "The team".
- Reason: Option B (cheering) correctly turns the trailing phrase into a participial modifier describing the team's ongoing actions. Option A creates a comma splice. Option C lacks a comma-conjunction balance, and Option D ruins the timeline. [1]
Question 3
Designed with a touch screen and high-resolution camera, ________. Which choice best completes the sentence?
- A) the new smartphone is a favorite among tech enthusiasts.
- B) tech enthusiasts love the new smartphone.
- C) the display of the new smartphone is impressive.
- D) the manufacturer created it to be the best device.
Answer: A
- Diagram Action: Draw arrow forward from "Designed with" to the noun after the comma.
- Reason: The smartphone is the object that was designed with a screen and camera. Tech enthusiasts (B) and the manufacturer (D) are people, not phone designs. The display (C) is just a part of the phone, not the entire device that was designed.
Question 4
The intense winter storm knocked down several power lines across the county, ________ thousands of residents without electricity. Which choice best completes the sentence?
- A) left
- B) and it left
- C) leaving
- D) which leaving
Answer: C
- Diagram Action: Draw arrow backward from the blank to the main action "knocked down".
- Reason: Option C (leaving) is a trailing participle that perfectly illustrates the immediate cause-and-effect relationship of the storm's action. Option A creates a run-on/verb-tense clash, Option B lacks proper coordination punctuation, and Option D is ungrammatical. [1]
Question 5
Having grown up in a rural village, ________. Which choice best completes the sentence?
- A) the bustling city felt completely overwhelming to me.
- B) I found the bustling city completely overwhelming.
- C) the sights and sounds of the bustling city were new to me.
- D) an urban lifestyle was difficult to adjust to.
Answer: B
- Diagram Action: Draw arrow forward from "Having grown up" to the noun after the comma.
- Reason: The pronoun "I" is the only subject capable of growing up in a village. The city (A), the sights (C), and the lifestyle (D) cannot grow up in a village, making them dangling modifiers.