阻力最小的方向, 最容易的途径

off-line

Roser-Nelaton line

jump a queue; cut a line

casting weight fishing line (line)

英国，ＵＫＡＥＡ\nCulham On-line Signle Experimental Console\nCOSEC\n核

line focus tube

built-in smokemeter【环境】;in-line smokemeter【环境】

coaxial line tube