名词 quad:

1. one of four children born at the same time from the same pregnancy

2. a muscle of the thigh that extends the leg

3. (printing) a block of type without a raised letter; used for spacing between words or sentences

4. a rectangular area surrounded on all sides by buildings

quadvt.用空铅填abbr.四边形（=quadrangle)abbr.四组；四胞胎之一（=quadruplet)abbr.四声道的（=quadraphonic）abbr.四头肌（=quadriceps）abbr.空铅；铅块（=quadrat）n.四方院子；四胞胎之一；嵌条；成套的四件东西Quadalti夸达尔蒂quadroden.四极管Quadrari夸德拉里Quadrini夸德里尼quadrics二次型quadroomn.黑人血统占四分之一的人quadrupl[医] 四倍quadrandn.象限; 直角扇面Quadrani夸德拉尼Quadbeck夸德贝克

1. This works the quads and the hamstrings.
   这组动作锻炼四头肌和腿筋。
2. Contract your quads by gently pressing your thighbones down into the floor.
   通过轻轻地将大腿骨压向地面来收缩股四头肌。