the front line ⇒ 他一直在科研第一线工作。 Tā yīzhí zài kēyán dìyīxiàn gōngzuò. → He's always worked on the front line of scientific research.

light

( 指人 ) mole

front line

outside line

aerial

( 电磁波 ) ray

artery

feeder

curve

( 指电话或电报 ) hotline ⇒ 这个广播电台开通了观众热线。 Zhège guǎngbō diàntái kāitōngle guānzhòng rèxiàn. → This radio station has opened an audience hotline.

( 边界 ) boundary

straight line

( 地理 ) latitude

( 指绘画 ) line

clue

( 指交通 ) route

( 丝线 ) floss

route

( 指眼睛 ) line of vision

( 指交通 ) route

line of defence ( 英 ) 或 defense ( 美 )

front line

horizon ⇒ 地平线上有一条船。 Dìpíngxiàn shang yǒu yī tiáo chuán. → There is a ship on the horizon.

meridian

diagonal

( 字 ) fuse

zebra crossing

radio

streamlined

production line

lifeblood

ultraviolet ray

infrared rays pl

Wi-Fi

cable TV