diff --git a/internal/phraser/acks.go b/internal/phraser/acks.go
index 20c0be4..4a6f6dd 100644
--- a/internal/phraser/acks.go
+++ b/internal/phraser/acks.go
@@ -65,7 +65,7 @@ var ackKeys = []string{
 
 // ackFloor — the literal each key falls back to when the file is unusable.
 // These are the exact strings that lived in Go before this file existed.
-var ackFloor = registerFloor(map[string]string{
+var ackFloor = map[string]string{
 	AckFact:          "записала факт.",
 	AckFactKey:       "отметила: {key}",
 	AckFactValue:     "отметила: {key} = {value}",
@@ -90,7 +90,7 @@ var ackFloor = registerFloor(map[string]string{
 	FailAck:          "не получилось отметить.",
 	FailSnooze:       "не получилось отложить.",
 	FailQuiet:        "не получилось переключить тихий режим.",
-})
+}
 
 // Acks picks a hand-written Russian acknowledgement. Safe for concurrent use.
 type Acks struct{ d *deck }
@@ -119,7 +119,7 @@ func LoadAcks(src rand.Source) (*Acks, error) {
 // deck reads through a nil *Acks, which is the unloadable-file case.
 func (a *Acks) deck() *deck {
 	if a == nil {
-		return nil
+		return floorDeck(ackFloor)
 	}
 	return a.d
 }
diff --git a/internal/phraser/deck.go b/internal/phraser/deck.go
index 1f53745..9136775 100644
--- a/internal/phraser/deck.go
+++ b/internal/phraser/deck.go
@@ -35,8 +35,8 @@ type deckFile struct {
 	Entries       map[string]deckEntry `json:"entries"`
 }
 
-// deck picks a line. Safe for concurrent use. A nil *deck answers from the
-// floor, which is what an unloadable file leaves behind.
+// deck picks a line. Safe for concurrent use. A deck with no entries answers
+// from the floor, which is what an unloadable file leaves behind (floorDeck).
 type deck struct {
 	mu    sync.Mutex
 	rnd   *rand.Rand
@@ -90,7 +90,7 @@ func (d *deck) text(key string, vars map[string]string) string {
 	tmpl := ""
 	if d != nil {
 		if e, ok := d.file.Entries[key]; ok && len(e.Variants) > 0 {
-			tmpl = d.pick(key, e)
+			tmpl = d.pick(key, fillable(e.Variants, vars))
 		}
 	}
 	if tmpl == "" {
@@ -129,12 +129,67 @@ func (d *deck) variants() []string {
 	return out
 }
 
+// fillable narrows variants to the ones this call can actually say, which is
+// the rule an optional placeholder needs: a caller with nothing to put in
+// {tail} must not be handed a variant that has one. Two passes, because both
+// halves matter. The first keeps only variants whose every placeholder has a
+// non-empty value, so an absent optional never reaches him as braces. The
+// second prefers, among those, the variants using the most of what the caller
+// supplied, so a caveat he was given is not dropped for a shorter wording.
+// Nothing fillable leaves the list alone, and the unfilled placeholder shows
+// up in the answer rather than turning it into silence.
+func fillable(variants []string, vars map[string]string) []string {
+	if len(variants) < 2 {
+		return variants
+	}
+	best, bestUsed := make([]string, 0, len(variants)), -1
+	for _, v := range variants {
+		used := 0
+		ok := true
+		for _, ph := range placeholders(v) {
+			if vars[ph] == "" {
+				ok = false
+				break
+			}
+			used++
+		}
+		if !ok || used < bestUsed {
+			continue
+		}
+		if used > bestUsed {
+			best, bestUsed = best[:0], used
+		}
+		best = append(best, v)
+	}
+	if len(best) == 0 {
+		return variants
+	}
+	return best
+}
+
+// placeholders lists the {name}s in tmpl, in order.
+func placeholders(tmpl string) []string {
+	var out []string
+	for {
+		i := strings.IndexByte(tmpl, '{')
+		if i < 0 {
+			return out
+		}
+		j := strings.IndexByte(tmpl[i:], '}')
+		if j < 0 {
+			return out
+		}
+		out = append(out, tmpl[i+1:i+j])
+		tmpl = tmpl[i+j+1:]
+	}
+}
+
 // pick chooses at random, skipping whatever this entry said last time.
-func (d *deck) pick(key string, e deckEntry) string {
+func (d *deck) pick(key string, variants []string) string {
 	d.mu.Lock()
 	defer d.mu.Unlock()
 
-	choices := e.Variants
+	choices := variants
 	if len(choices) > 1 {
 		fresh := make([]string, 0, len(choices))
 		for _, v := range choices {
@@ -151,24 +206,23 @@ func (d *deck) pick(key string, e deckEntry) string {
 	return got
 }
 
-// floorOf reads the Go literal behind key, and works on a nil deck because that
-// is exactly the case it exists for. The per-family map is the source of truth.
+// floorOf reads the Go literal behind key. Every deck carries its own family's
+// map, including the floor-only deck an unloadable file leaves behind, so no
+// lookup ever crosses families. It used to go through one global map keyed by
+// bare entry name, which two families both calling an entry query_unknown
+// silently shared: whichever registered last answered for both (Vikunja #521).
 func floorOf(d *deck, key string) string {
-	if d != nil && d.floor != nil {
-		return d.floor[key]
+	if d == nil {
+		return ""
 	}
-	return deckFloors[key]
+	return d.floor[key]
 }
 
-// deckFloors — every family's floor literals in one map, so a nil deck still
-// finds them. Families register at init; the keys are namespaced by family.
-var deckFloors = map[string]string{}
-
-func registerFloor(floor map[string]string) map[string]string {
-	for k, v := range floor {
-		deckFloors[k] = v
-	}
-	return floor
+// floorDeck — the deck a family falls back to when its file will not load. It
+// has no entries, so every read drops through to the floor literals, and it is
+// a real *deck so no accessor has to know which case it is in.
+func floorDeck(floor map[string]string) *deck {
+	return &deck{last: map[string]string{}, floor: floor}
 }
 
 // fill substitutes {name} for each var. A placeholder with no value is left
diff --git a/internal/phraser/fallbacks.go b/internal/phraser/fallbacks.go
index a9c7058..2124242 100644
--- a/internal/phraser/fallbacks.go
+++ b/internal/phraser/fallbacks.go
@@ -39,12 +39,12 @@ var fbKeys = []string{fbChat, fbQueryUnknown, fbQuerySources, fbWorldGap}
 
 // hardFloor — the literal each key falls back to when the file is unusable.
 // These are the exact strings that lived in Go before this file existed.
-var hardFloor = registerFloor(map[string]string{
+var hardFloor = map[string]string{
 	fbChat:         "даже не знаю, что сказать.",
 	fbQueryUnknown: "не знаю.",
 	fbQuerySources: "вот что я нашла: {sources}",
 	fbWorldGap:     "сейчас не могу ответить — большая модель недоступна, а придумывать не хочу.",
-})
+}
 
 // Fallbacks picks a hand-written Russian fallback line. Safe for concurrent use.
 type Fallbacks struct{ d *deck }
@@ -66,7 +66,7 @@ func LoadFallbacks(src rand.Source) (*Fallbacks, error) {
 // deck reads through a nil *Fallbacks, which is the unloadable-file case.
 func (f *Fallbacks) deck() *deck {
 	if f == nil {
-		return nil
+		return floorDeck(hardFloor)
 	}
 	return f.d
 }