Identify the root
Expand, expense, and expensive share a family — know which form you need.
vocabulary game · 3–5 min
Word family builder
From a root in the text, choose the related form that correctly completes a sentence.
How to play word family builder
Word family builder trains morphology — how roots grow into related forms. From a word in the passage, you choose the noun, verb, or adjective form that correctly completes a new sentence. Recognizing families multiplies vocabulary. One root unlocks several forms, which speeds decoding and improves precision on fill-in and grammar-tinged reading items. Helpful for academic vocabulary and readers learning English morphology patterns.
Fit the sentence slot
A blank before a noun often wants an adjective; a subject slot may want a noun.
Keep meaning aligned
Right part of speech with wrong sense still fails.
Tips for word family builder
Habits that make this game transfer to real reading and official tests.
Say the sentence aloud
Awkward rhythm often means the wrong form.
Combine with context clues
Meaning first, then morphology.
Collect families as you read
Note two related forms whenever you meet a tough academic word.
Frequently asked questions
Answers about word family builder, what it trains, and how to improve.
A set of related words built from the same root, such as decide, decision, and decisive.
You recognize more words faster and choose precise forms when meaning is close but grammar differs.
Both — morphology sits between vocabulary and sentence structure.
Related games and drills
Keep training nearby skills, then measure whether the improvement transferred.
Measure progress
Test comprehension
Games train skills in short rounds. Official results still come from the tests.
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