首先

First, switch back to the front panel by selecting Show Front Panel from the Window menu.

首先，切换到前面板（通过选择Window菜单中Show Front Panel的）。

Mark the line on back panel and at the marked line drill four holes on back panel.

我们首先在背板上划好线并在划线位置用电钻在背板上打四个孔，然后用冲击钻打孔。

First, we propose an improved image super-resolution system based on iterative back projection.

首先，我们根据叠代投影方法提出改进的超解析影像系统。

It doesn't make any sense,because the first thing the builders would have done after getting down here was cut a secondary shaft back out for air...

因为当建造这里的人到这里以后，他们首先会做的事，应该是建造一个二级通风口来获取空气，以防发生坍塌的状况

"Well,first of all,we'd better go back to the video shop."

"好的，首先，我们最好回到这个音响店。"

Firstly, based on natural gradient and nonlinear principle component analysis, a matrix equation is obtained by block recursive updating, and then the matrix equation is solved by using QR factorization and back substitution to obtain the optimal separating matrix.

首先基于自然梯度和非线性主分量分析，构造出按块递归更新的矩阵方程，然后用QR分解和回代法逐块求解该矩阵方程得到最优分离矩阵。

First, can we agree that it's a big back yard?

首先，我们对"那是一个很大的后院"能达成一致吗？

First,skin regions are detected based on YCbCr model of skin color;each block is morphologically processed in order to smooth out the biconvex and small backdate and to fill holes.Then,skin regions are segmented.At last,a disk template is used to find the location of eye and mouth.

方法首先根据YCbCr肤色模型检测出肤色区域；用数学形态学的膨胀和腐蚀方法进行肤色处理，平滑了边界，同时消除了肤色块的连通；再利用圆盘结构元素对人脸区域做闭运算，从而得到人眼和嘴的位置。

First, we've got a good political backdrop.

首先，我们有很好的政治环境。

First of all, know this, anyone can play in the backfield, but to be a GOOD back player is probably one of the hardest things in paintball.

首先， 你必须知道，任何人都可以做后卫，但是要成为一个好的后卫很可能是漆弹里最难做到的事之一。

I'm strongly against the death penalty — it's an eye for an eye.

我不赞成死刑——这是以牙还牙的报复行为。

And to get you the support you need, we're enlisting all elements of our national power: our diplomacy and development, our economic might and our moral suasion, so that you and the rest of our military do not bear the burden of our security alone.

并给你们所须的支援，我们正徵召国家所有各种的力量：我们的外交及发展，我们的经济力量与道德劝说，所以你们与其他军人不须要孤独地负起国家安全的责任。