Breakdown of Вам нужно срочно заполнить эту анкету.
этот
this [f: эта, n: это]
вам
to you (formal/plural)
нужно
it is necessary
срочно
urgently
Questions & Answers about Вам нужно срочно заполнить эту анкету.
Why does the sentence start with Вам instead of Вы?
This is the standard Russian way to express "need to" or "have to". It is an impersonal construction literally meaning "To you it is necessary." The person who needs to do the action is put in the Dative case, so вы (you) becomes вам, followed by нужно and the infinitive verb заполнить.
Can I use надо instead of нужно in this sentence?
Yes, absolutely! Вам надо срочно заполнить эту анкету means exactly the same thing. When followed by a verb infinitive to express obligation, надо and нужно are perfectly interchangeable.
Why is the ending эту анкету instead of эта анкета?
These words are in the Accusative case because they act as the direct object of the verb заполнить (to fill out). The feminine noun анкета changes its ending to -у, and the matching word for "this" (эта) changes to эту.
Why do we use the perfective verb заполнить instead of the imperfective заполнять?
We use the perfective aspect because the focus is on a single, completed result. You need to finish filling out the form from start to finish. If the sentence were about a recurring habit (like "you always need to fill out forms"), you would use the imperfective заполнять.