短语词组短語Counter -sunk head 埋頭;靜心counter -sunk square neck bolt 埋頭方頸螺栓d counter -sunk bolt 平頂埋頭螺栓flat -headed counter-sunk bolt 平頂埋頭螺栓half -counter-sunk rivet head 半埋頭式鉚釘頭counter sunk head 埋頭 返回 counter sunk