expand: may apply whether the increase comes from within or without and regardless of manner, whether by growth, unfolding, or addition of parts: our business has ~ed with every passing year.


amplify: implies the extension or enlargement of something that is inadequate: ~ the statement with some details.


swell: implies gradual expansion beyond a thing's original or normal limits: bureaucracy ~ed to unmanageable proportions.  limit限度极限表示不能越过的点a point beyond which something cannot go


distend: implies outward expansion caused by pressure from within: a stomach ~ed by gas.  


inflate: implies distension by or as if by the introduction of a gas or something insubstantial and suggests a resulting instability and liability to sudden change: an ~d ego.     如Stuart jumped into the sea and inflated the liferaft斯图尔特跳到海里给救生艇充气，本身表示通货膨胀，指价格上涨导致货币价值下降，如to control/curb inflation控制/抑制通货膨胀


dilate: applies especially to the expansion of diameter and suggests a widening of something circular: dim light causes the pupils of the eyes to ~.  直径  如red wine can help to dilate blood vessels红葡萄酒有助于扩张血管


expand扩大: 泛指扩大，无论生长展开增加，无论受内力外力，amplify扩充: 指将不足的扩展增大，swell肿胀: 指超出了正常限度，distend膨胀: 指受到内部压力而扩大，inflate充气膨胀: 指充入气体或轻质物而膨胀，导致不稳易变，dilate扩大: 多指圆形物变宽


记忆方法: 1）首字母EASDID想成SEA DID海的行为纳百川<==扩大           "扩"的意思是"推广伸张放大"，如扩大扩展扩散扩建扩张扩军扩充扩容等。来源未说明。"胀"从月长声，表示和身体有关，本义"皮肉鼓胀"。现有2个意思 1、体积变大，如膨胀肿胀热胀冷缩通货膨胀 2、身体内壁受到压迫而产生不舒服的感觉，如肚子胀胃胀

     2）扩大的意思是增大尺寸体积mean to increase in size or volume.