on that [this] score
((略式))その［この］点については
on the (other) end of the line
（電話の）向こう側に
on the 4th of January＝on January 4＝((英))on 4 January
１月４日に（◆後者はそれぞれon January (the) fourth，((英))on the fourth of Januaryと読む）．
on the afternoon of July 1
７月１日の午後に
On the air
((掲示))放送中
on [over] the airwaves
放送で
on the alert
油断［抜け目］なく
on the assumption that ...
…という前提で
on the basis of [that] ...
…に基づいて
on the beam
船の真横に
