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Updated: 2026年5月31日
String Concatenation
Original task (JA): 文字列の結合
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Conclusion
String Concatenation — free browser-based JavaScript practice
Why it matters in real projects
+で文字列を結合できます。 Similar patterns appear daily in code review and production UI work.Step-by-step workflow
1. Read the guide and understand the goal of "String Concatenation" 2. Review the JavaScript editor pane and start from the starter code 3. Open hints if stuck; compare your diff with the sample solution 4. Click Run and inspect preview/console output 5. Auto-check looks for output containing: 山田, 太郎. 6. After success, continue with adjacent exercises in the same categoryCore concept explained
+で文字列を結合できます。Technical focus
Key JavaScript APIs: console.log.Hint before you peek at the solution
firstName + ' ' + lastName または テンプレートリテラルSample solution walkthrough
JavaScript APIs used: console.log. Verify spelling and async/await usage. Explanation: +で文字列を結合できます。 Hint recap: firstName + ' ' + lastName または テンプレートリテラルSolution code
📝 Sample code
const firstName = '山田';
const lastName = '太郎';
console.log(firstName + ' ' + lastName);Common mistakes for this exact task
・Skipping the hint: firstName + ' ' + lastName または テンプレートリテラルTroubleshooting
Q: Preview does not change after Run A: Ensure you edited the JavaScript pane and clicked Run. Q: Looks correct but check fails A: Auto-check looks for output containing: 山田, 太郎. Look for typos, full-width spaces, or unclosed tags. Q: Console shows errors A: Open DevTools Console and fix bracket/quote mismatches at the reported line. Q: Hard to type on mobile A: Use landscape mode or continue on desktop—the same URL keeps progress in localStorage.Interview / portfolio tips
・Explain the techniques in "String Concatenation" in your own words within 30 seconds ・Practice walking through each line of the sample solution on a whiteboard ・Connect this task to a real component you would ship ・Mention responsive or accessibility trade-offs ・Describe when you use: console.logWhat to do after you pass
Move to the next exercise in the js-basic track, then continue the learning roadmap at /en/learning/js-basic/.Keywords
Free hands-on exercise covering 文字列の結合, js-basic, 初級, console.log, string concatenation—search-friendly guide for String Concatenation.🧪 Try it here — safe to break things
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Jump to editor■ Exercise task
firstNameとlastNameを結合して「山田 太郎」とconsole.logで出力してください。
Hint if stuck
firstName + ' ' + lastName または テンプレートリテラル