threefoleadj.三倍；增加二倍；三重的；三方面的；三次adv.三倍；增加二倍；三重地；三方面的；三次threenum.三n.三；三个adj.三个的three-wheel landing三轮着陆three station printer三态打印机three-pin conncetor三脚连接器three hundred and two(=302) 三百零二three-level storage三级存储three days' sensationthree leaf flag hinge三叶尼龙垫圈铰链three-quarter crown四分之三冠, 部分罩冠three-furrow plough三铧犁three-way connector三通接线夹