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急に， きゅうに
1. swiftly, rapidly, quickly, immediately, hastily, hurriedly
2. suddenly, abruptly, unexpectedly
3. sharply (of a slope, bend, etc.), steeply
迅速地、快速地、快些、立刻、匆忙地、急匆匆地；突然地；突然间；出乎意料地；(指斜坡、弯道等)陡峭地；陡直地
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活気付く， 活気づく， かっきづく
1. to become animated, to liven up, to become active
tbd
は
1. indicates sentence topic
2. indicates contrast with another option (stated or unstated)
3. adds emphasis
指示句子的主题；表示与另一选项（无论是否明确提及）形成对比；表示强调
