All my mind was centered on my studies, which, especially at the beginning, were difficult. In fact, I was insufficiently prepared to follow the physical science course at the Sorbonne, for, despite all my efforts, I had not succeeded in acquiring in Poland a preparation as complete as that of the French students following the same course.
Thinking is easy, acting is difficult, and to put one's thoughts into action is the most difficult thing in the world.
In actuality, there was casting for the show and it was pretty difficult.
Conversation between Adam and Eve must have been difficult at times because they had nobody to talk about.
A lot of my research time is spent daydreaming - telling an imaginary admiring audience of laymen how to understand some difficult scientific idea.
Each success only buys an admission ticket to a more difficult problem.
I dealt with legal questions in the interest of Adolf Hitler and the NSDAP and its members during the difficult years of struggle for the victory of the Movement.
Adult stem cells are also problematic, as they are difficult to identify, purify and grow, and simply may not exist for certain diseased tissues that need to be replaced.
However, writing software without defects is not sufficient. In my experience, it is at least as difficult to write software that is safe - that is, software that behaves reasonably under adverse conditions.
Unions can play a valuable role in large organisations where it is difficult to talk to a thousand people. They can negotiate annual pay awards with management, represent grievance cases, and explain and advise on complicated changes in employment or pension law.
Difficult as it is really to listen to someone in affliction, it is just as difficult for him to know that compassion is listening to him.
To be famous these days with no grounding and no substance is not especially difficult. I urge you instead to seek to be relevant, to be agile and educated.
I love writing and do not know why it is considered such a difficult, agonizing profession.
You'll find individuals agreeing on this, but when they get into collective societies and larger groups they find it difficult to achieve group agreement.
The most difficult thing for us to do is to mitigate and offset our agricultural emissions. If we find a way to do that, then we're showing other countries how to do it, too.
The problem with airports is that we go there when we need to catch a plane - and because it's so difficult to find the way to the gate, we tend not to look around at our surroundings.
Alas! how difficult it is not to betray one's guilt by one's looks.
Albania is at risk and we are living in difficult times.
It is hard to convince a high-school student that he will encounter a lot of problems more difficult than those of algebra and geometry.
It is difficult to know how the Tudors actually spoke because we're going back before Shakespeare; much of the drama from that period is courtly, allegorical.