Our survey revealed that these allergies were mainly one-offs.是什么意思？

Our survey revealed that these allergies were mainly one-offs.

我们的调查显示这些过敏多为一次性反应。

our

pron. 我们的，we的所有格形式，<口>我们家，敝；

例句
Roland was taken aback by our strength of feeling...
我们反应如此强烈，令罗兰大吃一惊。

survey

vi. 测量土地；vt. 调查，勘测，俯瞰；n. 调查（表），调查所，测量，测量部，测量图，概观，检查，鉴定书，环顾；

例句
With the caveat that almost every figure in this survey is suspect, it can at least be said that the world travel and tourism industry is huge...
尽管事先声明此项调查报告中的每个数字都不可靠，但至少可以说，世界旅游观光业的市场庞大。

revealed

v. 显示( reveal的过去式和过去分词 )，揭示，泄露，[神学]启示；

例句
Laurie revealed she had booked herself a flight home last night.
劳丽透露她昨晚已为自己预订了返家的机票。

that

det. 那个，那；pron. 那个，那；conj. 多么，如此…以至，用于某些动词、形容词和名词后，引出各种从句；adv. 不那么，那样；

例句
...expensive make-up that we saw being advertised by a beautiful model...
我们所见的由一位漂亮模特代言的昂贵化妆品

these

adj. 这些的；pron. 这些；

例句
There's lots of money about these days for schemes like this.
近来这类计划资金充足。

allergies

n. [医]过敏症，[口]厌恶，反感，（对食物、花粉、虫咬等的）过敏症( allergy的名词复数 )，变态反应，变应性；

例句
Food allergies can result in an enormous variety of different symptoms...
食物过敏会引发很多不同的症状。

were

be的过去时复数和第二人称单数形式，有时代替 was,用于条件从句、动词 wish 之后等；

例句
Shops, houses, and vehicles were set ablaze.
店铺、房子和车辆全都陷于火海。

mainly

adv. 大部分地，主要地，基本上；

例句
Thousands of people, mainly Zulus, assembled in a stadium in Thokoza...
数以千计的人，主要是祖鲁族人，聚集在托考查的一个体育场里。