Like me, you're going to have to concentrate upon the army as a way to the top.
I went away, and tried to concentrate upon my work for the next few days.
To concentrate upon one would be to give opportunity to the other.
It was hard for him to concentrate upon any one voice.
One must concentrate upon the present and forget the past.
It was the first time that he had concentrated upon any single picture in the group.
I could not concentrate my mind upon the papers in front of me.
My life from this moment became highly concentrated upon itself.
They were able to concentrate upon the task of becoming a teacher.
Some light, however, was breaking through one of them, so I concentrated my attention upon this.