1. 崩溃：drop the reins of government 下台 | drop through 崩溃 | drop to one's knees 迫使某人屈服

2. 崩溃, 失败：drop throat 沉降式流液洞. | drop through 崩溃, 失败. | drop to 下降到. 跌到.

3. 落空,失败：cut through 穿过,凿穿 | drop through 落空,失败 | fall through 失败,落空

4. 滴穿：droppingmercuryelectrode 滴汞电极 | drop-through 滴穿 | drop-weighttest 落重试验