stationary 与 stationery
stationary 是形容词,意为"固定的"．"静止不动的"： The bus remained stationary .
Our profit have remained stationary .
stationery 是名词，意为"文具纸张"The things a stationer sells are called stationery.
为更好地区分 stationary 与 stationery 这两个词，建议先记住 stationer (文具商)这个词，再把stationer 与 stationery 联系起来。
alternately 与 alternatively
alternately 意为两者交替或轮流；alternatively 指在两者或两者以上中选择其一。如：
The manager is alternately kind and severe .经理时而和蔼，时而严厉。
You may alternatively say lighted or lig or alight .
你可以说Lighted 或者 lit 或者 alight 三者任选其一。
