下面的有些词组是什么意思?

下面的有些词组是什么意思?
A New York City doctor who treated Ebola patients in West Africa became the first person to test positive for the virus
became the first person to test positive怎么不用被动语态?
New York Mayor Bill de Blasio said residents were safe to travel around the city,
这个to be 是说居民游览那座城市的时候是安全的
"There is no reason for New Yorkers to be alarmed. alarmed这个是被动语态吗?说的纽约居民没有理由（因为病毒）而被惊恐.

became the first person to test positive for the virus我觉得变成 become the first person tested positive for the virus 或者to be tested不可以吗

test这里作不及物动词,意思是[To exhibit a given characteristic（when subjected to a test）],
可理解为“呈现”,因此不需要作被动式.
She tested positive for AIDS.她呈现阳性（在对艾滋测试时）.
没有to be safe啊,是...residents were safe to travel...居民在城里流动是安全的.
travel这里主要指上下班、各种出行等,和旅游没有关系.
被动式的动词分词和过去分词作形容词在形式上一样,但语义上不同.理解的话,前者说的是一个动作被完成,而后者是描述一种状态.其实不用太纠结属于哪个,因为这根本不影响理解句子.
alarmed这里是作形容词,New Yorkers need not be scared (alarmed) by the virus or something.
翻译的没错.纽约居民没必要因为病毒而感到恐慌.（因为不是被动语态,所以不需要翻译“被”）
become the first person testing positive for the virus.不能用过去分词,因为会产生被动效果,test 作呈现,不需要改被动.用testing 或 to test都是可以的.