With the recent focus on customer privacy, door-knocking seems like an intrusion into other people's lives.

随着近来对客户隐私的重视，上门探访似乎成了对他人生活的入侵。此处，focus（注意力或兴趣的）中心，焦点（参见本单元注释3），为名词。例如：We shall maintain our focus on the needs of our community. 我们将继续重点关注社区的需求。

But those who try it for the first time are usually surprised by the pleasant reception they receive.

但是，第一次尝试的人们往往会为其受到的友好接待而感到惊讶。此句含有两个定语从句，第一个定语从句who try it for the first time修饰those；it上文中提到的door-knocking；for the first time第一次，首次，在句中作状语。例如：For the first time I felt regret and sorrow. 我第一次感到后悔和难过。... are usually surprised by the pleasant reception是整句话的谓语部分，为被动语态。they receive是第二个定语从句，修饰the pleasant reception，句中省略了关系代词which / that。

The easiest way to do door-knocking is to try your local area first. Being a neighbor creates an immediate connection with the person answering the door; after that, everything else is easy.

上门探访最容易的方式是从你所在的社区开始。邻居关系能让你与开门人之间很快建立起关系，之后的事情就好办了。being a neighbor（邻居/邻居关系）是动名词短语作句子的主语。例如：Writing an English composition is not easy. 写好英文作文并不简单。answering the door是现在分词短语作定语，修饰the person，可以写为定语从句the person who answers the door。例如：Do you know the young man waiting outside the school gate? 你认识等在校门口的那个年轻人吗？