advance guard

基本解釋

" is from the Greek and means "an advance guard".
一詞來自希臘語，意思是提前防衛(wèi)（預(yù)防）。
Mobile phones, it seems, are the advance guard for mobile-broadband networks that will extend internet access to the whole of mankind.
手機(jī)似乎已在幫助全人類接入移動寬帶網(wǎng)絡(luò)中扮演起了排頭兵的角色。
Uniformed military personnel patrolled Washington street corners, the advance guard of a massive security presence planned for the oath-taking, inaugural speech, parade and other festivities.
為了保障總統(tǒng)宣誓儀式，就職演講，游行和其他慶祝活動的開展，政府部署了大規(guī)模的安全力量。身穿制服的軍人在華盛頓的街角巡邏，他們是安保的前沿陣地。

The avant-garde (literal translation, advance guard) valiantly leads the rest of the culture into the uncharted future.
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And in areas such as Schengen, there can be little real objection to an advance guard plunging ahead.
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a military unit sent ahead of a main body to find gaps in enemy defences, clear away minor opposition, and prevent unexpected contact