In English phrases that follow certain patterns, I find it impossible to find any regularity in the usage of the definite article. I'll give an example in this post, hoping that someone might perhaps enlighten me about this problem. I have noticed that in phrases that follow the pattern "last year's <noun>," the native speakers never use the definite article in front of "last." For example, the construct "the last year's winner" would sound definitely wrong. However, the definite article is normally used in front of phrases that follow the very similar pattern "previous year's <noun>" -- for example, "the previous year's winner" sounds perfectly right. A Google search for each of these phrases with and without the definite article confirms my observations. So, what would be the relevant difference between these phrases? The standard sets of prescriptive rules for article usage suggest that both phrases should be preceded by the definite article, since each one represents a definite reference to a singular noun -- but apparently this is not the case in practice. There are many other cases similar to this one. For example, "the" often stands in front of nouns qualified by "previous" -- but never in front of those qualified by "yesterday's." Am I ignorant about some general rule that holds in these cases, or am I perhaps failing to understand the proper application of the well-known standard rules here? Or must one really memorize the usage of articles in all such phrases on a case-by-case basis? Thanks in advance for your replies.