困难的问题以前总是需要用笔和纸工作数小时.Difficult problems used to take hours of work with pencil and paper.请你把那个记一下, 好 吗 ?(指用笔或在脑中记下来)Please make a note of that, will you ?他的线描是彩色的, 他的用笔也是彩色的.His line drawing is of color, his pencraft is ...