The tongue (3) extends from the front end of the base member (1) and is used to wedge under the staple crossbar (11).

舌状片(3)从基板件(1)的前端延伸出来，并用于楔入到钉书钉横条(11)之下。

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Unfortunately, the Leica's take-up spool needs a long tapering tongue of film, which users must wedge under a spring clip on the spool's barrel before manually wrapping a few turns of film around it.

ECONOMIST: A die-hard analog photographer goes digital