All at once the threads that moved them seemed to grow weak and tangled ; and it was all difficult . and uncle nikolay stood before them in a stern and menacing attitude 突然，引导他们的线松弛了，纠缠在一起，拉也拉不动了，此时，尼古拉姑父突然站在他们面前，神态威严可怖。
2.
An effective discritized scheme based on staggered grids is provided by deeply studying the construction and implementation of difference scheme on non - uniform and staggered grids . coupling of velocity and pressure is solved by simple method ; the boundary conditions and relations of velocity and pressure are analyzed in details 深入研究交错非均匀网格的差分方案的构造与实施，基于交错网格提出了有效离散格式；采用simple算法对速度压力关系解耦，列举几种代数方程的求解办法，分析并阐述了逐线松弛技术。
