The toothbrush has a 'top- loading' structure in which the cartridge is housed in a recess at the brushend of the toothbrush handle, the recess being accessible by removing the brush head.
If you need to brush up, you will find the resources outlined at the end of this article helpful.
如果您需要重新温习,您会发现本文结尾处所列出的参考资料会对您有所帮助。
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Marketing as a conversation: Engagement with end users and customers through social computing, transforming marketing from broad-brush communication to thousands of individual conversations.