Time frame studio • present perfect practice — Construct have/has plus the supplied past participle and connect the sentence to an explicitly stated up-to-now or continuing time frame…

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<header><span class="eyebrow">Sentence studio / context first</span><h1>Connect the past to now.</h1><p class="intro">Build the requested form from the supplied choices, then check the sentence against its time frame.</p></header>
<nav class="controls" aria-label="Practice context"><button type="button" id="nora" class="secondary">1 · Nora</button><button type="button" id="kai" class="secondary">2 · Kai</button><button type="button" id="yesterday" class="secondary">3 · Yesterday</button><button type="button" id="plural" class="secondary">4 · Nora and Kai</button></nav>
<article class="context-card"><span class="eyebrow" id="time-label">Continuing situation</span><h2 id="context">Nora started work at the library in 2024 and still works there.</h2><svg viewBox="0 0 700 95" class="timeline" role="img" id="timeline" aria-label="Work begins in 2024 and continues through now, October 13, 2026."><line x1="45" y1="35" x2="650" y2="35" stroke="#c6d9d5" stroke-width="4"/><g id="timeline-marks"></g><text x="40" y="80">Past</text><text x="490" y="80">Now · Oct 13, 2026</text></svg><p id="timeline-caption" class="timeline-caption"></p><p id="target"><b>Requested form:</b> present perfect simple using work.</p></article>
<section class="panel"><h2>Build the sentence</h2><div class="sentence" id="sentence" aria-live="polite">Nora ___ ___ at the library since 2024.</div><div class="grid"><div><label for="aux">Auxiliary / no auxiliary</label><select id="aux"><option value="">Choose…</option><option value="has">has</option><option value="have">have</option><option value="none">No auxiliary</option></select></div><div><label for="verb">Supplied verb form</label><select id="verb"><option value="">Choose…</option><option value="worked">worked</option><option value="works">works</option><option value="working">working</option></select></div></div><div class="controls"><button type="button" id="check">Check this sentence</button><button type="button" id="retry" class="secondary">Clear choices</button><button type="button" id="reset" class="secondary">Reset practice</button></div><div id="feedback" class="feedback" aria-live="polite">Choose both parts, then check the requested construction.</div></section>
<details><summary>How this practice handles alternatives</summary><p>The first, second, and fourth cards request present perfect simple. Present perfect continuous can be valid in other contexts; it is outside these specified targets. The yesterday card explicitly requests simple past.</p><p>This page checks supplied choices against authored targets. It does not grade arbitrary prose, diagnose ability, or reject US simple-past uses merely because already, just, or yet appears.</p></details>
<footer>Fictional teaching contexts as of October 13, 2026. Original cards and reviewed targets stay with each prompt. Feedback is local and not saved or collected.</footer>
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const cards={nora:{subject:'Nora',context:'Nora started work at the library in 2024 and still works there.',target:'present perfect simple using work',tail:'at the library since 2024.',aux:'has',verb:'worked',options:['worked','works','working'],time:'Continuing situation',reason:'The work started in 2024 and continues now.',timeline:'Work begins in 2024 and continues through now, October 13, 2026.'},kai:{subject:'Kai',context:'Kai’s experience up to now includes two workshop visits; no finished date is specified.',target:'present perfect simple using visit',tail:'the workshop twice.',aux:'has',verb:'visited',options:['visited','visits','visiting'],time:'Experience up to now',reason:'The two visits belong to experience up to now; no finished date is given.',timeline:'Two workshop visits occurred before now, within experience up to October 13, 2026.'},yesterday:{subject:'Yesterday Nora',context:'Yesterday Nora finished putting labels on two boxes. The event is explicitly finished.',target:'simple past using label',tail:'two boxes.',aux:'none',verb:'labeled',options:['labeled','labels','labeling'],time:'Finished yesterday',reason:'Yesterday is an explicitly finished past time; this contrast asks for simple past.',timeline:'The labeling is bounded in yesterday, separate from now, October 13, 2026.'},plural:{subject:'Nora and Kai',context:'Nora and Kai’s experience up to now includes two workshop visits together; no finished date is specified.',target:'present perfect simple using visit',tail:'the workshop twice.',aux:'have',verb:'visited',options:['visited','visits','visiting'],time:'Plural subject · experience up to now',reason:'Nora and Kai is a plural subject, so use have plus the supplied participle visited.',timeline:'Two shared workshop visits before now, within experience up to October 13, 2026.'}};let current='nora';
function sentence(c,a,v){return c.subject+' '+(a==='none'?'':a?a+' ':'___ ')+(v||'___')+' '+c.tail}
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