In the early 80's, you have to carry out deep geophysical exploration, on this information more understanding, our students are very interested in this...
You have already started the deep geophysical exploration since the 1980s, and have a better understanding of the information on this respect in which our students are very interes...
You had already started deep geographical prospecting dated back to the 1980s; you have a better understanding of the information in this aspect, our students are very interested...
You have already carried out an Geophysical Exploration in advanced in the earily 80s, and you should have much more grasp on this respect. Our students are very enthusiast with it...
