单语范例（未经PONS编辑处理）
The game also introduces to the series optional side games such as midair refuelings, which are available before and after certain missions.
en.wikipedia.org The pools are clothing optional and family friendly.
en.wikipedia.org Unlike in referendums, voting in a plebiscite has traditionally been optional.
en.wikipedia.org Optional items include a large panoramic glass roof with electric roller blind, running boards, automatic tailgate, and an electrically-operated trailer coupling.
www.irishexaminer.com A passenger-side wiper and sun visor, and a heater were available as optional extras.
en.wikipedia.org 互联网提供的例句（未经PONS编辑处理）
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io.uni-paderborn.de Information at sign-up Day trip to Düsseldorf Includes: city tour, a visit to a typical bar with a free drink ( Altbier or non-alcoholic drink ), optional: museum visit ( please bring your semester ticket! )
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Stadtführung, Besuch einer typischen Kneipe mit einem Freigetränk ( Altbier oder nichtalkoholisches Getränk ), optional: Museumsbesuch ( Semesterticket mitbringen! )
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www.ntbb.de For the VD4-ST only optional available components such as DC / DC-converter, memory expansion for the data logger, sensor measurement range adaption and terminal clamps for 16 inputs are integrated parts of the VD4-ST2. The VD4-ST2 has particularly been designed as a top hat rail mountable version for use in plant engineering and beyond.
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Die ursprünglich für das Fernwirkgerät VD4-ST optional erhältlichen Zusatzbaugruppen DC / DC-Wandler, Speichererweiterung für den Datenlogger, Sensoranpassung und Klemmen für 16 Eingänge sind bereits im Grundgerät VD4-ST2 enthalten.
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www.central-strapping.de In addition, the optional available accessory for round bundling also allows in a simple way to strap quickly and reliably packages which have no or only very small contact face.
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Das optional verfügbare Rundumreifungszubehör ermöglicht zudem auf einfache Weise auch Packstücke schnell und zuverlässig zu umreifen, die keine beziehungsweise nur sehr geringe Auflagefläche haben.
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musescore.org This step is optional, but highly recommended.
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Dieser Schritt ist optional aber dringend empfohlen.
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www.uni-bielefeld.de Microphone and discussion facilities ( optional: simultaneous interpreting )
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Mikrofonie- und Diskussionsanlage ( optional: Simultanübersetzungen )