Clockwork Clues Reading Passage
Grade 4 • Reading & Morphology Vocabulary Quest
Clockwork Clues
Name:
Date:
Target Prefixes:
un- = not / opposite re- = again / back dis- = not / opposite pre- = before mis- = wrong / badly non- = not / without
The Mystery of the Inventor's Vault
Read carefully to follow Leo's adventure in the workshop.
Leo stood quietly before the heavy brass door of his grandfather’s workshop. To prepare for this morning’s expedition, he had packed a pocket magnifying glass, a brass wrench, and a leather notebook. Beside him, his mechanical robotic puppy, Sprocket, let out an unusual series of clicks. Grandfather had misplaced the brass key months ago, but Leo noticed a notched gear hidden behind the nameplate. With a gentle twist, the mechanism gave an unexpected click, releasing the latch to uncover an enormous room of spinning gears and copper dials.
Inside, slender steam pipes hissed rhythmically, and a miniature brass automaton hammered away nonstop upon a tiny copper drum. Leo followed strict family precautions, treading carefully so he would not stumble over copper wires. "Do not distrust your instincts, Sprocket," Leo whispered. On the central mahogany table rested Grandfather's grand invention: the Chrono-Dial. Taped beside it was an old journal entry: "I originally misjudged the pressure limits, but once I rebuilt the main escapement valve, the clockwork turned smoothly."
Suddenly, Sprocket yelped as a rubber tube popped free, causing the primary pressure regulator to disconnect! The quiet humming turned into a wild, screeching clatter—pure mechanical nonsense. Leo needed to predict which valve would shut off the steam before the system overloaded. He could not afford to miscalculate the pressure, or the gears would jam forever.
Instead of panicking, Leo paused to reread the blueprint schematic on the wall. "The bronze lever!" he cheered. He gripped the lever firmly and hauled it down. The hissing steam began to disappear, and the wild rattling quieted. Carefully, he pressed the ignition switch to restart the cooling fan. Sprocket wagged his brass tail in triumph. Leo smiled proudly, thrilled that patience and keen observation had helped him unlock the secrets of the vault.
Detective Word Log: Find a word in the story for each prefix! Write one word you discovered:
un-
re-
dis-
pre-
mis-
non-
Page 1 of 2 • Reading Passage Turn page to complete Comprehension & Prefix Activities →
Part II
Comprehension & Prefix Analysis
Score: / 24 pts
Section A: Story Comprehension
1. What main challenge threatens Leo and Sprocket inside the workshop?
A Grandfather locked them inside the vault forever.
B A regulator disconnected, threatening a pressure overload.
C The mechanical puppy ran out of copper wire.
D The blueprint schematic on the wall was missing.
2. How was Leo able to open the locked workshop door without the master key?
A He pried the brass hinges off with his wrench.
B He turned a notched gear hidden behind the nameplate.
C Sprocket found an unlatched maintenance pipe.
D The clockwork automaton unlocked it from the inside.
3. Why was it critical for Leo to reread the blueprint diagram instead of guessing? Use evidence from the story.
4. What does Leo's reaction to the sudden steam emergency reveal about how he solves problems?
Section B: Prefix Breakdown Chart
Deconstruct each word from the passage into its prefix, base word, and complete meaning.
Target Word
Prefix
Base Word
Meaning in Story Context
miscalculate
nonstop
disconnect
precautions
Section C: Prefix Master Application
5. Write the letter of the correct prefix next to each definition:
Wrongly or badly
Before in time
Not or without
[A] non- [B] mis- [C] pre-
6. Sentence Challenge: Choose one word with the prefix un- and one word with the prefix re- from the story. Write one complete sentence using both words correctly.
Page 2 of 2 • Morphology & Comprehension Assessment Prefix Focus: non, mis, re, pre, dis, un
