The part of a sentence "gain a grasp" is correct and usable in written English.
It means to obtain understanding or knowledge about something. It is often used in the context of learning or comprehending new information. Example: "Students must work hard to gain a grasp of complex mathematics concepts."
The number of minutes that Uwe Rösler has managed in English football, during which time he has ably guided Brentford to fourth in League One (albeit having collected three wins against opposition in the bottom seven) and swiftly gained a grasp of what the division is all about.
By looking at these critical historical moments, we will also gain a firmer grasp of contemporary problems surrounding nationhood in France and around the world.
All trainees gain a basic grasp of reporting principles and information verification as well as a chance to develop story ideas.
Who is to say, then, that Americans' opinions wouldn't change were they to gain a better grasp of what the law entails?
Keen to gain a fuller grasp of its depth and nature, he put up posters throughout Kampala in June 2009 announcing a "workshop" on the issue in a local school.
Frederick Ahl and Hanna M. Roisman believe that contemporary readers who do not know ancient Greek can gain a sophisticated grasp of the Odyssey if they are aware of some of the issues that intrigue and puzzle the experts.
Dr. Ricketts argues that students in the United States, which has its roots in Western tradition and culture, need first to gain a firm grasp of their heritage as Americans before they move on to understanding their ethnic or racial heritage.
About 10 years ago, in an effort to gain a better grasp on McCone's world, I took up the hobby of building fully electrified scale models, first of the legal cooperative where she started out and then of her own brown-shingled cottage, a pursuit that the more tactful of my friends label unusual, and that the more blunt refer to as obsessive.
