According to Professor Johnson, we don't have to read the book if we don't want to, as it is optional.
根据约翰逊教授的说法，我们不想读这本书，就不必读，因为它是选读的。
It is optional but useful to model partitions.
建模划分是可选的但是有用的。
You don't have to take this course , for it is optional .
你不一定非要修这门课，它是选修的。
Although it is optional, this standard recommend treating warnings as errors in debug builds as well.
虽然是可选的，本标准也推荐在调试版中将警告作为错误。
In case a virtual shard id map is not provided (it is optional), it is defaulted to the physical shard id map.
如果未提供虚拟碎片ID映射(可选)，默认为物理碎片id映射。
When studying in Radio, TV and Correspondence School in London, he often did homework carefully, even it is optional.
他在伦敦那所广播、电视与函授大学学习时，常常认真做家庭作业，甚至连自由选作题也作了。
Once you’ve signed up for this (and it is optional, at least for now) you don’t need to do anything else to “share” your activity with Facebook.
一旦你同意注册了这个功能（这是可选的；至少目前是），你想分享你的活动的时候，你不需要做任何事。
It is optional on servo system, driving system, working platform and dust collection device. Besides, full version of authentic software would come with the machine.
可选配伺服系统、传动系统、工作台面、吸尘装置，赠送全套正版软件。
Sex education is a sensitive area for some parents, and thus it should remain optional.
性教育对一些家长来说是个敏感的话题，因此应该还是非强制性的。
It is said that in England death is pressing, in Canada inevitable and in California optional.
据说，在英国死亡是迫在眉睫的，在加拿大死亡是不可避免的，在加州是可以选择的。
That is optional; the profile author does not have to import it.
这是一个可选项; 创建概要文件不用必须导入它。
It provides optional, automatic capture of screens as a macro is being recorded in the Host Terminal.
在主机终端记录一个宏时，它提供了可选的，自动化的屏幕截图功能。
The QEMU accelerator is an optional step, but I recommend it because it results in greater performance.
QEMU加速器是一个可选步骤，但我建议执行这一步骤，因为它会带来更优的性能。
The submission rule is optional; you need it only if you want to submit just the data instance instead of the entire form.
提交规则是可选的；只有在希望提交数据实例而不是整个表单的情况下，才需要提交规则。
If the optional start is specified, it indicates the character position in the source-string at which the search is to begin.
如果指定了可选的起始位置，则表明它是源字符串中开始进行搜索的字符位置。
The containment attribute is optional, but if an object is contained, it gets serialized along with its container.
containment属性是可选的，但是如果某个对象是被包含的，那么它就和其容器一起被序列化。
When you're importing a namespace from a file, you will see a schemaLocation attribute on the XSD import statement, but it is an optional attribute.
当您从一个文件导入命名空间时，将看见XSD导入语句中的 schemaLocation属性，但这是一个可选属性。
It is always optional to re-state any base interface in a partial class.
分布类中是否重新声明它所实现的接口也是可选的。
Option -d is optional as it shows verbose information on its working.
选项-d是可选的，因为它会显示关于afs令牌的工作原理的冗长信息。
Use of an attachment object store is optional, and it involves considerable planning before you can implement it in Lotus Domino.
使用附件对象存储是可选的，在Lotus Domino中实现它之前，需要充分地加以计划。
This step is optional; it is required only for Lotus Sametime 8.5 interoperability.
该步骤是可选的；只用于LotusSametime 8.5互操作性。
You can ensure that SSL is used for IIOP by indicating that it is required, and not optional, on the CSIv2 inbound transport panel.
可以通过在CSlv2入站传输面板中指明SSL是必需而不是可选的，从而确保对IIOP使用 SSL。
Assessment is not the goal (though it may be an optional byproduct).
评估不是目的(尽管它可能是可选的副产品)。
It is not an error (because the declaration is optional), but it might be worth noting.
它不是错误(因为声明是可选的)，但是它可能值得注意。
Its use is optional, meaning that a resource adapter is not required to implement it.
它的使用是可选的，这意味着资源适配器不一定非得实现它。
While this stereotype is most definitely optional, it may help you identify elements of a model — that are not services themselves — as clients of services.
当这个原型是明确的最优的时，它可能帮你识别模型的元素——这不是服务本身——作为服务的客户。
Finally I press the paper for a little while under a weight, this is optional but I find it gives good results.
最后，把这叠纸放在重物下压一小会，这一步不是必需的，但是我觉得效果很显著。
For SOA to be successful, SOA business and technical governance is not optional, it is required.
对于SOA的成功，SOA业务和技术治理不是可选的，而是必须使用的手段。
For SOA to be successful, SOA business and technical governance is not optional, it is required.
对于SOA的成功，SOA业务和技术治理不是可选的，而是必须使用的手段。
应用推荐