At the end of four trials, feedback was given.

在四次试验结束的时候会给出反馈。

youdao

But unlike in the dolphin experiment, the monkeys had to complete four trials before they got any feedback.

但与海豚实验不同的是，猴子们必须完成四项实验才能得到反馈。

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The remaining four trials were of adequate methodological quality.

其余四项试验方法的质量是充足的。

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It was the last of four trials over the death of Sofyen Belamouadden, 15, of Acton, west London.

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After four trials lasting 21 months, three have been convicted of murder, five of manslaughter, including Bayode, 12 of lesser charges and three cleared.

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Four more trials of patients who took Vioxx for more than 18 months are expected soon, she writes, and other risks of heart attack did not deter the ruling.

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