alone: [13] Although partly disguised by its pronunciation, alone is in fact simply a compound of all and one (whose /wun/ pronunciation began to develop around the 15th century). In Old English it was a completely separate phrase, all āna, literally ‘completely by oneself’, but by the 13th century this had coalesced into a single word. Loss of its initial ain the 14th century gave rise to the adjective lone. => all, lone, one
alone (adj., adv.)
c. 1300 contraction of all ane, from Old English all ana "unaccompanied, all by oneself," from all "all, wholly" (see all) + an "one" (see one). Similar compounds are found in German (allein) and Dutch (alleen).
权威例句
1. If you're lonely when you're alone, you're in bad company.--Jean Paul Sartre
如果你独处时感到寂寞,说明没有把自己陪好。
2. Don't leave a child alone in a room with an open fire.
房间里有裸露的明火时,不要让孩子独处其中。
3. He knew when to leave well alone and when to interfere.
他知道什么时候该适可而止,什么时候该插手干预。
4. He had always been an outcast, unwanted and alone.
他一直都被视为异类,无人理睬,形单影只。
5. He was working alone and did not have an accomplice.