dyn,dynamo来源于希腊语的dynames,意为"power"。
1.dynamic
adj.forceful,having a lot of energy;of physical power and forces;producing motion精力充沛的；充满活力的；动力的 *dyn (=power)
例句：Bollinger construction ,a dynamic Brazilian contractor,is aggressively pursuing the deal.一个充满活力巴西承包商——宝灵戈建筑公司，也正在角逐这项合同，且很竞争力。
2.dynamite
n.powerful explosive used in mining and quarrying;any person or thing having a spectacular effect 炸药；会引起轰动的人或物 *dyn(=power)
例句：Dynamite was used to clear the fallen rocks quickly.炸药曾被用于快速清理落下的岩石。
3.dynamo
n.machine for converting mechanical energy to electrical energy;an energetic person 发电机；精力旺盛的人 *dyn (=power)
例句：Fortunately,I have a real dynamo for a secretary.很幸运我有一个精力旺盛的秘书。
4.dynasty
n.succession of rulers belonging to one family 王朝 *dyn(=power)
例句：The dynasty was short-lived though,lasting only to Myhari's great grandson's succession to the throne in 1463.但是，这个王朝寿命很短，只维持到1463年马哈里的曾孙登上王位。