提问几天了,还是一个回答,纳闷.也许是觉得原文写得不错吧!不过,以相互探讨为出发点,我还是表达一些建议：句子结构没太大问题,但表达方式可以再改进,使文章更流畅.
某些用词也有斟酌的余地.如：
有或含有不一定是用 had, 可以用其他同义词替代,使句子更生动.
Mastered the usage of GPS….. 你是指掌握运用GPS或其使用技巧,而usage 一般是指东西的用途、用法,所以换成 application 或use 较合适.
至于 skill,作为名词,当然复数可以加s; 不过,在a systematic geological skills training…., 这个skill 已不能当名词加s,因为training才是名词了；所以一楼的说法是对的.例子：information technologies 可以有s, information technology industry 就不能加s了.
只是一些浅见,仅供参考.
1. It’s a preliminary cognitive fieldwork of geology consisting direct knowledge of stratum, igneous rock and geomorphy (such as karst, river, delta, seashore, etc.). This geological fieldwork was an integration of theory and practice, so it was very useful in the enhancement of the thoughts and skills of fieldwork.
2. It’s a systematic geological skill training that covered a comprehensive study of the outdoor features of various stratums (也可以用复数 strata), rocks and structures (fold and fault). From the training, I had learnt the method of collecting rock samples, geological profile survey and geological mapping, as well as mastered the application of GPS PDA and mapping software. The most important benefit I had gained was the recognition of the value of teamwork and the meaning of the school motto, “Hard work and plain living; realistic and pragmatic”.
【英语牛人团】1. 1和2 都是在解释您受过的培训内容，it's和that只要不是用得太频繁没什么不妥。其实，可以将两句连起来（请看下面）。2. 有问题。句子貌似您able to communicate with professional literature，与专业文学交流？？3. 没有这种定性要求。简历主要是让招聘者看明白，了解你。如果没把握写得流畅，可以用排列式，以1，2, 3......将学历与经验列出来。It’s a preliminary cognitive fieldwork of geology consisting direct knowledge of stratum, igneous rock and geomorphy (such as karst, river, delta, seashore, etc.)； so it was very useful in the enhancement of the thoughts and skills of fieldwork.This systematic geological skill training incorporated an integration of theory and practice which covered a comprehensive study of the outdoor features of various stratums (也可以用复数 strata), rocks and structures (fold and fault). It also provided practicals on the method ofrock sample collecting, geological profile survey and geological mapping, as well as the application of GPS PDA and mapping software. The most important benefit I had gained was the recognition of the value of teamwork and the true meaning of the school motto, “Hard work and plain living; realistic and pragmatic”.