8th Grade Infinitives Printable Worksheets for Grammar Practice

These 8th grade infinitives printable worksheets move students past the surface-level task of finding a to + verb pattern and into the more demanding work of explaining what an infinitive phrase actually does in a sentence. That's the grade 8 expectation — not just identification, but function analysis — and most students need repeated practice across varied sentence types before that skill becomes reliable.

Skills These Worksheets Build

Each worksheet covers the full arc of infinitive competency at the eighth-grade level, from basic phrase recognition through syntactic function analysis. Students underline infinitive phrases, sort them against prepositional phrases that open with to, label each phrase's grammatical function, and revise or extend sentences by constructing infinitive phrases of their own.

• Identify infinitives and infinitive phrases in complete, varied sentences
• Sort to phrases — infinitive or prepositional — based on the word that immediately follows
• Label grammatical function: noun, adjective, or adverb
• Rewrite sentences by adding or strengthening an infinitive phrase
• Analyze a short paragraph and annotate every infinitive phrase by function

The paragraph-level analysis task deserves particular attention. When students can move from marking a phrase in an isolated sentence to identifying the same structure in a paragraph they didn't write, they've crossed from drill into observation — and that's where grammar understanding begins to transfer into actual reading and writing work.

Frequent Errors Worth Watching in Student Work

The most common error is treating every to phrase as an infinitive. Students develop this habit because it's right often enough to feel reliable — until they hit a sentence like She walked to the auditorium to present her findings. Both phrases begin with to, but only the second is an infinitive. Teaching students to check the word immediately after to — is it a base verb? — is faster and more durable than asking them to memorize definitions. What makes 8th grade infinitives printable worksheets valuable here is the deliberate mixing of both structures within the same exercise. When students see infinitives and prepositional phrases side by side in a set, they have to apply the check rather than pattern-match on autopilot.

Function labeling produces its own persistent errors. Students who correctly identify to win in She trained for months to win the competition will frequently label it a noun because the phrase feels like "the important thing." It is actually functioning as an adverb, modifying the verb trained. The noun function confuses students in the opposite direction — To finish the project was her goal often gets labeled as an adverb because it opens the sentence and feels like a describing element. A quick substitution check works well here: can you replace the entire phrase with it or this? "It was her goal" still holds together, which confirms the noun reading. That check gives students a repeatable process instead of another rule to forget.

How to Build These Worksheets Into Your Lesson Plans

The format of 8th grade infinitives printable worksheets — clear directions, contained tasks, included answer keys — means they require almost no setup and slot into multiple instructional moments. The most productive placement depends on where students are in the learning sequence.

• Bell ringers: Two or three mixed sentences — some infinitive phrases, some prepositional — take about five minutes before instruction begins and give students daily low-stakes exposure without eating into the lesson.
• Right after direct instruction: The ten minutes immediately following a modeling session are when guided practice has the most traction. A short identification-and-sort worksheet keeps momentum going without losing the class to a device transition.
• Intervention groups: Pull the identification and sorting worksheets for students still shaky on the basic distinction. Function labeling can wait until that foundation is solid.
• Writing workshop: After students produce a first draft, a worksheet asking them to analyze infinitive phrases in mentor paragraphs shifts grammar from abstract exercise to craft decision.
• Exit tickets: Two function-labeling questions at the end of class take three minutes and produce formative data without sacrificing instructional time.

One classroom move worth building in deliberately: walk through the full decision process out loud under a document camera before students work independently. "I see to, the next word is compare, that's a base verb, so this is an infinitive phrase — now what job is it doing in this sentence?" shows students the reasoning, not just the answer. Students who skip that step and copy correct responses tend to show up weeks later in writing with the same errors the worksheet was meant to address.

Standard Alignment

These worksheets address CCSS.ELA-LITERACY.L.8.1.a, which asks students to "explain the function of verbals (gerunds, participles, infinitives) in general and their function in particular sentences." The verb explain in that standard matters — it sets a higher bar than simple identification. Students must connect the infinitive form to a specific grammatical role in a specific sentence, which is exactly what function-labeling and sentence-revision tasks train. The standard sits within the broader L.8.1 conventions strand, so the revision tasks in this set also reinforce sentence-level writing control as students add and refine infinitive phrases in their own prose.

Adjusting the Work for Different Readiness Levels

Students who are still uncertain about basic sentence structure — what a verb phrase is, what a modifier does — need identification and sorting worksheets first, with shorter sentences and no more than one infinitive phrase per example. A two-column sort (infinitive phrase / prepositional phrase) before function questions arrive keeps frustration manageable and builds the footing students actually need before analysis is possible.

On-level students move through identification, sorting, and function labeling in sequence and handle paragraph analysis well by the end of the unit. Students ready for more challenge can write original sentences using infinitives in all three functions, then exchange papers for partner labeling — which forces them to articulate their choices rather than simply execute them. Pulling a paragraph from the current class novel and asking students to annotate every infinitive phrase by function takes the skill fully off the worksheet and into authentic reading, which is a strong indicator of real transfer.

Frequently Asked Questions

What prior knowledge do students need before beginning these worksheets?

Students should have a working understanding of basic parts of speech — particularly verbs and nouns — before tackling function-labeling tasks. The identification and sorting worksheets require less background knowledge and work well even when students are encountering infinitives for the first time.

How do I sequence the worksheets across a unit?

Move in this order: identification first, then sorting (infinitive versus prepositional phrase), then function labeling, then sentence revision and paragraph analysis. Skipping the sorting step is the most common sequencing mistake — students who can't reliably distinguish infinitives from prepositional phrases will produce mostly guesswork on function questions.

Are these worksheets meant for guided instruction or independent practice?

The 8th grade infinitives printable worksheets in this set work best as guided practice immediately after direct instruction, and as independent practice once students have completed at least one modeled round. Using them without any prior instruction consistently produces frustration rather than learning — particularly on the function-labeling tasks, where students have no decision routine to fall back on.

Do the worksheets come with answer keys?

Yes. Each worksheet includes a corresponding answer key. For function-labeling tasks, the keys flag sentences where more than one interpretation is defensible, so teachers have the context they need to run a real discussion rather than simply marking responses right or wrong.