In rhetoric a parenthesis or parenthetical clause is an explanatory phrase or just one word inserted into the sentence. Such phrase may be omitted without loosing a sense of passage, however parentheses may better describe it or express attitude of the speaker or writer to events or person. Parenthesis often treated as modifier phrases but often do not carry any syntactical role at all. They are often expressed by adverbials, conjunctions and impersonal clauses.

Typical applications of parenthesis include:

• Modal meaning with words like “probably”, “certainly”, “for sure”, “must be”;
• To express ordinary behavior with phrases like “as usual”, “sometimes”;
• Source of information expressed with phrases like “it's said”, “some say”, “do you think”, etc.;
• The way of expressing thoughts and attitude to it: “let's be honest”, “in other words”, “in sum”, “in a nutshell”;
• The call to another person in conversation to draw attention: “do you understand (that)…”, “get this”, “believe it or not”, “picture that”, “you see”, etc.;
• Function similar to conjunctions, to express cause and/or (con)sequence of actions: “by the way”, “for example”, “it means”, “beside this”;
• To show speaker's feeling to events: “luckily”, “fortunately”, “thank god”, “sad to say”, “I fear”, etc.;
• Express strong feeling, including interjections: “between you and me”, “joking apart”, “”;

Any longer dependent clause describing the person or action of main sentence may be used similarly as parenthesis. For example:

• “Uglûk sitting in the corner - he was usually silent in public places - suddenly, started his long and loudly speech.” = translation needed;
• “I was trying to hold on the rock with my frozen hands - I already knew that they started to rot of cold burn - in a desperate try to survive” = translation needed;

Of course, such long sentences belong to fiction literature and do not occur in normal conversation being not very suitable for Orcs' speech.

Such phrases should be separated by punctuation marks in written speech. But Tengwar or Cirth are limited with them. It's suggested to use “two vertical dots” (means comma but look like colon) in Cirth.