"Carrying water in a sieve" is an idiomatic expression that refers to a pointless or futile activity. There are several synonyms for this expression that are commonly used in English language. One of the most popular synonyms is "beating a dead horse" which means to waste time and effort on something that is already finished or impossible. Another alternative is "pouring water into a leaky bucket" which refers to a fruitless task that yields no results. Other synonyms for "carrying water in a sieve" include "drawing water from an empty well," "chasing a wild goose," and "trying to catch smoke with your hands." Regardless of the variation used, the message conveyed is one of futility and wasted effort.