The other half discovered the container was empty—and realized the tester had fooled them.

另外一半（孩子）发现容器是空的，并意识到测试员欺骗了他们。

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I've discovered that half of the platforms at Stratford International are not the right height and are being raised to make them suitable for the High Speed (HS1) Javelin trains.

BBC: Stratford platforms raised to host Javelin trains

It points to a study which discovered that half the ads during children's TV programs were from food companies and that many promoted breakfast cereals, soft drinks, savory snacks, confectionery and fast food.

FORBES: Fat Food Fight On Two Fronts

Another time the investigators discovered that roughly half the top executives of a company were unindicted co-conspirators in a fraudulent deal.

FORBES: Gotcha: Pushing The Limits of Due Diligence