Ovaj tjedan na poslu je stresan.

to be

Breakdown of Ovaj tjedan na poslu je stresan.

• posao: work
• na: at
• ovaj: this

Questions & Answers about Ovaj tjedan na poslu je stresan.

Why is it tjedan and not another form like tjedna or tjednu?

Tjedan is in the nominative singular because it is the subject of the sentence: Ovaj tjedan = this week.
Other forms like tjedna (genitive) or tjednu (dative/locative) are used when the week is not the subject but is governed by a preposition or verb, e.g. tijekom ovog tjedna (during this week), u ovom tjednu (in this week – rarer, more formal).

What case is na poslu, and why is that form used?

Na poslu is locative singular of posao (job, work).
The preposition na + locative is used to express being at a place:

• na poslu – at work
• na fakultetu – at (the) university
  So posao changes to poslu in the locative.

What is the difference between posao and poslu?