同根派生 英汉例句A thumb index. 拇指索引He's nipped his thumb in the fastener. 他的姆指被扣件夹住了。He have a painful cut on his thumb. 他拇指上的伤口疼。Don't suck your thumb; it's so dirty. 别舔手指头，太脏了。She prodded me on the shoulder with her thumb. 她用大拇指在我肩上戳了一下。