Some topics are general and are regarded as 'classical' because they are always relevant across time periods through being relatable even as time progresses. For example, topics or themes about politics and satire would still prevail until now. Other topics or themes (such as viral videos) are only for that particular event and do not always occur, thus they do not prevail in the long run.
1st blank : a title ; 2nd blank: label
Answer:
A shallow
Explanation:
Something that is described as shallow is "of little depth". The initial description given of the canal is that of a body of water that was not deep enough to allow the passage of large ships. To solve this problem of the canal being shallow, dredgers had to be used to reach the bottom of the canal, thus increasing the depth of the canal.
After this was done, an improvement was seen in the increased number of ships plying the canal water body.