To create a set of 20 interactive quizzes and fill in the blank exercises for learning Spanish, you can leverage the power of HTML tags to create engaging and interactive content. Below, I have provided an example of how you can structure your quizzes and exercises using HTML tags.

1. Multiple Choice Quiz: Use the <ul> and <li> tags to create a list of options. Wrap the correct answer in a <strong> tag for emphasis. Here's an example:

<p>What is the Spanish word for "hello"?</p><ul><li><input type="radio" name="question1" value="option1"> Hola</li><li><input type="radio" name="question1" value="option2"> Adiós</li><li><input type="radio" name="question1" value="option3"> Gracias</li><li><input type="radio" name="question1" value="option4"><strong>Buenos días</strong></li></ul>```

2. Fill in the Blank Exercise:
Use the `<input>` tag with the `type="text"` attribute to create a blank space for users to input their answers. Here's an example:

```html
<p>Translate "I love you" to Spanish:</p><p><input type="text" name="question2"></p>```

3. Matching Exercise:
Use the `<select>` and `<option>` tags to create a dropdown menu for users to match the correct translations. Here's an example:

```html
<p>Match the Spanish words with their English translations:</p><select name="question3"><option value="option1">Manzana (Apple)</option><option value="option2">Perro (Dog)</option><option value="option3">Gato (Cat)</option><option value="option4">Libro (Book)</option></select>

Remember to repeat the above examples for the remaining questions to create a set of 20 interactive quizzes and exercises.

To make your quizzes and exercises truly interactive, you can use JavaScript to validate the answers and provide feedback to the user. Additionally, you can style your quizzes using CSS to make them visually appealing.

For further references and resources on creating interactive quizzes and exercises with HTML, you may find the following links helpful:

• HTML Forms - Learn about different form elements in HTML.
• HTML Input Types - Explore the various input types you can use for quizzes and exercises.
• CSS Selectors - Understand how to style your quizzes using CSS selectors.

By following these guidelines and utilizing HTML tags effectively, you can create a set of engaging and interactive quizzes and exercises to aid in your Spanish learning journey.