1. 幻想;错觉
    An illusion is a false idea or belief.

    e.g. Do not have any illusions that an industrial tribunal will right all employment wrongs...
           不要幻想一个劳资仲裁法庭能纠正所有的雇佣不公现象。
    e.g. No one really has any illusions about winning the war.
           没有人幻想能赢得这场战争。

2. 假象;幻象
    An illusion is something that appears to exist or be a particular thing but does not actually exist or is in reality something else.

    e.g. Floor-to-ceiling windows can give the illusion of extra height...
           从地板直抵天花板的窗子会给人以高出实际距离的幻觉。
    e.g. This eerie calm is an illusion.
           这种怪诞的平静是一种假象。