He gave us a warning against placing confidence in people we did not know.

他告诫们, 不要们不了解的人。

Zollner's illusion makes parallel lines seem to diverge by placing them on a zigzag-striped background.

将平行线置于锯齿形条纹背景，左氏错觉会让平行线看来不平行。

The unit is composed of hydraulic and double conic placing,hydraulic spading and drawing ,straightening,shearing,end stopping,coiling,feeding,dropping cart,ect.

本机组有液压,双锥放,液压铲头引头,送,校直,剪切,阻尼,收卷,,小车等主要部件组成.

One of the big disincentives to placing weapons in space has been the technical difficulty and cost of such an enterprise.

一直以来，在太空部署武器的主要障碍之一就是技术难度以及该项事业的高昂成本。