Questions & Answers about Необходимо пить воду каждый день.
Why is “воду” in the accusative case?
“Воду” is the direct object of the verb пить (“to drink”). In Russian, direct objects go into the accusative case. The noun вода (water) is feminine, and its accusative singular form is воду.
What part of speech is “Необходимо” and why is it used here?
“Необходимо” is a short-form neuter adjective (often called an impersonal predicate). It functions like “it is necessary” in English. Because there is no explicit subject, the sentence is impersonal: “It is necessary to drink water every day.”
Why do we use the imperfective infinitive “пить” instead of a perfective form?
The imperfective infinitive пить describes a habitual or repeated action (“drinking water daily”). A perfective form like выпить would emphasize the completion of a single event (“to drink up / finish drinking once”), which doesn’t fit a routine/general recommendation.
Could we replace “Необходимо” with “Нужно”?
Yes. Нужно is less formal but equivalent in meaning. So you could say Нужно пить воду каждый день with no change in the overall meaning.
Why is there no explicit subject like “you” or “we”?