Initially, they were wary of Simon.是什么意思？

Initially, they were wary of Simon.

开始时他们对西蒙小心提防。

initially

adv. 开始，最初；

例句
He was initially articled to a solicitor.
他最初订约给一位律师当学徒。

they

pron. 他/她/它们，人们，大家，政府，当局，她们；

例句
The storms had abated by the time they rounded Cape Horn.
他们绕过合恩角时，暴风雨已经减弱。

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。

wary

adj. 谨慎的，小心翼翼的，警戒的，警惕的；

例句
The blackbird had a quick, wary look in case the cat was anywhere around...
这只乌鸫迅速警惕地张望了一眼，以防那只猫就在附近。

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

Simon

n. 西蒙（男子名）；

例句
When he returned, she and Simon had already gone...
他回来时，她和西蒙已经走了。