翻译练习 Translation

Google的暑期实习生中的当届毕业生，超过90%都得到了毕业后加入Google的工作邀请。
Among the summer interns of Google, after graduating, more than 90% of them got the invitations.

More than 90% of Google's summer interns recieved job offers after their graudation.

麦可斯(Mycos)教育数据咨询公司为大学毕业生所做的调查分析均清楚表明：毕业生的实习对就业率的贡献排在第一位。
According to the Mycos's survey about graduated students,the analyses show that intern experiences contribute to the employment rate at most.

According to the Mycos's survey of university graduates, those with internship experience have the highest rate of employment.

90%以上的美国学生四年里会实习2~3次。
In the USA, More than 90% students have their intern experiences 2-3 times during the college period.

In the US (In the USA is also correct, but we usually just write US), over 90% of  college students participate in 2-3 internships during their studies.

Note: Most of your gramar is pretty good. However, since this is a translation exercise, I think that overall flow is important as well, which is why I rewrote the sentences to sound more natural to a native speaker. I hope it helps!