新增默写功能，播放按钮移到导航栏，输入框改为下边框样式

LearnEnglish/LearnEnglish/Models/Quiz.swift

@@ -4,6 +4,7 @@ enum QuizMode: String, Hashable {
     case enToZh = "英选汉"
     case zhToEn = "汉选英"
     case spelling = "拼写"
+    case dictation = "默写"
 }
 
 struct QuizSetupRequest: Hashable {
@@ -48,7 +49,7 @@ enum QuizGenerator {
         switch mode {
         case .enToZh: return word.word
         case .zhToEn: return word.meaning
-        case .spelling: return word.meaning
+        case .spelling, .dictation: return word.meaning
         }
     }
 
@@ -56,7 +57,7 @@ enum QuizGenerator {
         switch mode {
         case .enToZh: return word.meaning
         case .zhToEn: return word.word
-        case .spelling: return word.word
+        case .spelling, .dictation: return word.word
         }
     }
 

LearnEnglish/LearnEnglish/Views/DictationInputView.swift

@@ -0,0 +1,64 @@
+import UIKit
+
+final class DictationInputView: UIView, UITextFieldDelegate {
+    var onChange: (() -> Void)?
+    var onSubmit: (() -> Void)?
+
+    private let textField = UITextField()
+    private let bottomLine = UIView()
+
+    var text: String { textField.text?.trimmingCharacters(in: .whitespaces) ?? "" }
+    var isEmpty: Bool { text.isEmpty }
+
+    override init(frame: CGRect) {
+        super.init(frame: frame)
+        textField.borderStyle = .none
+        textField.font = .systemFont(ofSize: 28, weight: .bold)
+        textField.textAlignment = .center
+        textField.autocorrectionType = .no
+        textField.autocapitalizationType = .none
+        textField.spellCheckingType = .no
+        textField.keyboardType = .asciiCapable
+        textField.placeholder = "输入完整单词"
+        textField.delegate = self
+        textField.returnKeyType = .done
+        textField.addTarget(self, action: #selector(textChanged), for: .editingChanged)
+
+        bottomLine.backgroundColor = .separator
+        bottomLine.translatesAutoresizingMaskIntoConstraints = false
+
+        addSubview(textField)
+        addSubview(bottomLine)
+        textField.translatesAutoresizingMaskIntoConstraints = false
+        NSLayoutConstraint.activate([
+            textField.topAnchor.constraint(equalTo: topAnchor),
+            textField.bottomAnchor.constraint(equalTo: bottomAnchor),
+            textField.centerXAnchor.constraint(equalTo: centerXAnchor),
+            textField.leadingAnchor.constraint(greaterThanOrEqualTo: leadingAnchor, constant: 16),
+            textField.trailingAnchor.constraint(lessThanOrEqualTo: trailingAnchor, constant: -16),
+            textField.widthAnchor.constraint(greaterThanOrEqualToConstant: 200),
+            textField.heightAnchor.constraint(equalToConstant: 48),
+
+            bottomLine.leadingAnchor.constraint(equalTo: textField.leadingAnchor),
+            bottomLine.trailingAnchor.constraint(equalTo: textField.trailingAnchor),
+            bottomLine.bottomAnchor.constraint(equalTo: textField.bottomAnchor),
+            bottomLine.heightAnchor.constraint(equalToConstant: 1.0 / UITraitCollection().displayScale),
+        ])
+    }
+
+    @available(*, unavailable)
+    required init?(coder: NSCoder) { fatalError() }
+
+    @objc private func textChanged() {
+        onChange?()
+    }
+
+    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
+        onSubmit?()
+        return false
+    }
+
+    func activate() { textField.becomeFirstResponder() }
+    func deactivate() { textField.resignFirstResponder() }
+    func reset() { textField.text = "" }
+}

LearnEnglish/LearnEnglish/Views/QuizViewController.swift

@@ -17,6 +17,7 @@ final class QuizViewController: UIViewController {
     private let speakerButton = UIButton(type: .system)
     private let optionsStack = UIStackView()
     private let spellingView = SpellingInputView()
+    private let dictationView = DictationInputView()
     private let spellingHintLabel = UILabel()
     private let resultLabel = UILabel()
     private let resultPhoneticLabel = UILabel()
@@ -48,6 +49,8 @@ final class QuizViewController: UIViewController {
         super.viewDidAppear(animated)
         if config.mode == .spelling, selectedOption == nil {
             spellingView.activate()
+        } else if config.mode == .dictation, selectedOption == nil {
+            dictationView.activate()
         }
     }
 
@@ -91,6 +94,13 @@ final class QuizViewController: UIViewController {
         nextButton.configuration = nextConfig
         nextButton.addAction(UIAction { [weak self] _ in self?.primaryButtonTapped() }, for: .touchUpInside)
 
+        navigationItem.rightBarButtonItem = UIBarButtonItem(
+            image: UIImage(systemName: "speaker.wave.2.fill"),
+            style: .plain,
+            target: self,
+            action: #selector(speakCurrentWord)
+        )
+
         let headerStack = UIStackView(arrangedSubviews: [progressView, countLabel])
         headerStack.axis = .vertical
         headerStack.spacing = 8
@@ -100,7 +110,7 @@ final class QuizViewController: UIViewController {
         promptStack.spacing = 12
         promptStack.alignment = .center
 
-        let inputStack = UIStackView(arrangedSubviews: [optionsStack, spellingView, spellingHintLabel])
+        let inputStack = UIStackView(arrangedSubviews: [optionsStack, spellingView, dictationView, spellingHintLabel])
         inputStack.axis = .vertical
         inputStack.spacing = 16
 
@@ -138,8 +148,11 @@ final class QuizViewController: UIViewController {
         resultPhoneticLabel.isHidden = true
 
         let isSpelling = config.mode == .spelling
-        optionsStack.isHidden = isSpelling
+        let isDictation = config.mode == .dictation
+        let isChoice = !isSpelling && !isDictation
+        optionsStack.isHidden = !isChoice
         spellingView.isHidden = !isSpelling
+        dictationView.isHidden = !isDictation
         spellingHintLabel.isHidden = !isSpelling
 
         if isSpelling {
@@ -153,6 +166,20 @@ final class QuizViewController: UIViewController {
             nextButton.isEnabled = false
             nextButton.isHidden = false
             spellingView.activate()
+        } else if isDictation {
+            dictationView.reset()
+            dictationView.onChange = { [weak self] in
+                guard let self else { return }
+                nextButton.isEnabled = !dictationView.isEmpty
+            }
+            dictationView.onSubmit = { [weak self] in
+                guard let self else { return }
+                primaryButtonTapped()
+            }
+            nextButton.configuration?.title = "确认"
+            nextButton.isEnabled = false
+            nextButton.isHidden = false
+            dictationView.activate()
         } else {
             nextButton.isHidden = true
             buildOptionButtons(for: question)
@@ -213,8 +240,18 @@ final class QuizViewController: UIViewController {
         showResult(typed == question.answer, for: question)
     }
 
+    private func submitDictation(_ typed: String, for question: QuizQuestion) {
+        guard selectedOption == nil else { return }
+        selectedOption = typed
+        if typed != question.answer {
+            wrongWords.append(question.word)
+        }
+        dictationView.deactivate()
+        showResult(typed == question.answer, for: question)
+    }
+
     private func showResult(_ correct: Bool, for question: QuizQuestion) {
-        if config.mode == .spelling {
+        if config.mode == .spelling || config.mode == .dictation {
             resultLabel.text = correct ? "正确" : "正确答案：\(question.answer)"
             resultPhoneticLabel.text = question.word.phonetic
             resultPhoneticLabel.isHidden = false
@@ -229,10 +266,18 @@ final class QuizViewController: UIViewController {
         nextButton.isHidden = false
     }
 
+    @objc private func speakCurrentWord() {
+        guard let question = current else { return }
+        speech.speak(question.answer)
+    }
+
     private func primaryButtonTapped() {
         if config.mode == .spelling, selectedOption == nil {
             guard let question = current, spellingView.isComplete else { return }
             submitSpelling(spellingView.typedWord(), for: question)
+        } else if config.mode == .dictation, selectedOption == nil {
+            guard let question = current, !dictationView.isEmpty else { return }
+            submitDictation(dictationView.text, for: question)
         } else {
             next()
         }
@@ -273,6 +318,8 @@ final class QuizViewController: UIViewController {
         showQuestion()
         if config.mode == .spelling {
             spellingView.activate()
+        } else if config.mode == .dictation {
+            dictationView.activate()
         }
     }
 }

LearnEnglish/LearnEnglish/Views/WordListViewController.swift

@@ -20,7 +20,8 @@ final class WordListViewController: UITableViewController {
         let quizMenu = UIMenu(title: "", children: [
             UIAction(title: QuizMode.enToZh.rawValue) { [weak self] _ in self?.startQuiz(.enToZh) },
             UIAction(title: QuizMode.zhToEn.rawValue) { [weak self] _ in self?.startQuiz(.zhToEn) },
-            UIAction(title: QuizMode.spelling.rawValue) { [weak self] _ in self?.startQuiz(.spelling) }
+            UIAction(title: QuizMode.spelling.rawValue) { [weak self] _ in self?.startQuiz(.spelling) },
+            UIAction(title: QuizMode.dictation.rawValue) { [weak self] _ in self?.startQuiz(.dictation) }
         ])
         navigationItem.rightBarButtonItem = UIBarButtonItem(title: "测验", menu: quizMenu)
     }