Exercise 1: An RSVP Form with TextField, Toggle & Stepper — Possible Solution
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struct RSVPForm: View {
    @State private var email = ""
    @State private var isSubscribed = false
    @State private var guestCount = 1

    var body: some View {
        Form {
            TextField("Email address", text: $email)
            Toggle("Subscribe to newsletter", isOn: $isSubscribed)
            Stepper("Number of guests: \(guestCount)", value: $guestCount, in: 1...10)
        }
    }
}

HOW IT WORKS: Three separate @State properties back the three real
input controls - email (a String for the TextField), isSubscribed (a
Bool for the Toggle), and guestCount (an Int for the Stepper). Each
control binds to its own property via the $ projected-value syntax,
exactly the same pattern used for @State throughout Chapter 6 - typing
in the TextField updates email, flipping the Toggle updates
isSubscribed, and tapping the Stepper's +/- controls updates
guestCount within its declared 1...10 range.

Form wraps all three controls in a real, natively-styled, grouped
container - the same visual treatment used throughout Settings-style
screens across Apple's own apps - with no extra layout code needed to
achieve that native appearance.

ANSWER: A Form containing a TextField bound to @State private var
email, a Toggle bound to @State private var isSubscribed, and a
Stepper (ranged 1...10) bound to @State private var guestCount
correctly gathers all three real pieces of RSVP input using the
standard @State/$ binding pattern.

WHY THIS WORKS AS AN ANSWER
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This correctly implements all three requested input controls inside a
Form, each backed by its own appropriately-typed @State property,
exactly matching the chapter's own established pattern.