To increase the usefulness of our generic code, instead of specifying the exact type of a generic type parameter, we can specify an upper (or lower) bound instead.
要提高泛型代码的有效性，可以指定一个上限（或下限），而不是指定某个泛型类型参数的精确类型。 这可以使用有界通配符来实现，它的形式为 “?
Proper design of sampling and survey methods can increase substantially the accuracy and usefulness of assessment data.
设计适当的抽样和调查方法，可以充分的提高评估数据的准确性，实用性。
Good drug administration procedures should ensure the smooth implementation of large - scale multi-center randomized controlled trials and increase their reliability and usefulness.
利用中心随机化系统在药品管理方面的优势，可以确保大样本多中心随机对照试验的顺利实施。
The introduction and seeming acceptability and usefulness of computers have somehow helped increase the efficiency of several firms.
计算机被介绍给人类，进而被人类接受和使用，这在某种程度上帮助提高公司的效率。
The introduction and seeming acceptability and usefulness of computers have somehow helped increase the efficiency of several firms.
计算机被介绍给人类，进而被人类接受和使用，这在某种程度上帮助提高公司的效率。
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