Simultaneous calls are not allowed because the call will immediately be disconnected by your Network Provider.

不能用多个卡同时打电话是因为电话会被网络供应商切断。

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WNaN mobile handheld radios that participated in multiple, simultaneous call groups and delivered situational awareness data despite communications disruptions.

10部WNaN移动手持无线电可在通讯中断时参与多次同时呼叫，提供态势感知数据。

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In Political Science, they call this "simultaneous discovery."

在政治学里,他们称之为同时期发现

耶鲁公开课 - 博弈论课程节选

The new 2.0 update features an entirely new FaceTime-like interface, allowing simultaneous audio translations within a video call, which not only adds a new interactive experience, but also adds another dimension to this new type of instant communication: the body language and tone to each conversation.

ENGADGET: Vocre 2.0 for iOS brings live translation to video calls

The simultaneous increase in many prices what we call inflation.

FORBES: How to Grow an Economy

As the leader in group video-chat, ooVoo's new mobile apps are the only major communications product offering users four simultaneous video streams at once on mobile devices, and hosting a total of up to 12 participants on one call, for free!

ENGADGET: ooVoo updates its iOS and Android apps to support four-way video calls