diff --git a/.gitignore b/.gitignore
index 7dda685..55927c0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@ github/
 gitlab/
 rss/
 factorial/
+dictionary/
diff --git a/matrix/commands.go b/matrix/commands.go
index 4263334..bd0d184 100644
--- a/matrix/commands.go
+++ b/matrix/commands.go
@@ -43,6 +43,7 @@ func (pc *ParsedCommand) parseCommandSyntax(command maubot.Command) error {
 	argumentEncountered := false
 
 	regexBuilder.WriteString("^!")
+	swBuilder.WriteRune('!')
 	words := strings.Split(command.Syntax, " ")
 	for i, word := range words {
 		argument, ok := command.Arguments[word]
@@ -50,8 +51,10 @@ func (pc *ParsedCommand) parseCommandSyntax(command maubot.Command) error {
 		if ok && len(word) > 0 /*&& word[0] == '$'*/ {
 			argumentEncountered = true
 			regex := argument.Matches
-			if argument.Required {
+			if !argument.Required {
 				regex = fmt.Sprintf("(?:%s)?", regex)
+			} else {
+				regex = fmt.Sprintf("(%s)", regex)
 			}
 			pc.Arguments = append(pc.Arguments, word)
 			regexBuilder.WriteString(regex)
diff --git a/matrix/matrix.go b/matrix/matrix.go
index 0bf5a01..18ec999 100644
--- a/matrix/matrix.go
+++ b/matrix/matrix.go
@@ -104,11 +104,11 @@ func (client *Client) GetEvent(roomID, eventID string) *maubot.Event {
 func (client *Client) TriggerCommand(command *ParsedCommand, evt *maubot.Event) maubot.CommandHandlerResult {
 	handlers, ok := client.handlers[command.Name]
 	if !ok {
-		log.Warnf("Command %s triggered by %s doesn't have any handlers.\n", command.Name, evt.Sender)
+		log.Warnf("Command `%s` triggered by %s doesn't have any handlers.\n", command.Name, evt.Sender)
 		return maubot.Continue
 	}
 
-	log.Debugf("Command %s on client %s triggered by %s\n", command.Name, client.UserID, evt.Sender)
+	log.Debugf("Command `%s` on client %s triggered by %s\n", command.Name, client.UserID, evt.Sender)
 	for _, handler := range handlers {
 		result := handler(evt)
 		if result == maubot.StopCommandPropagation {