Learn Farsi: این دانشمند فرانسوی بود که میکروب را کشف کرد. - It was the French scientist who discovered the microbe.

این دانشمند فرانسوی بود که میکروب را کشف کرد.in dâneshmand-e farânsavi bud ke mikrob râ kashf kard.

It was the French scientist who discovered the microbe.

Breakdown of این دانشمند فرانسوی بود که میکروب را کشف کرد.

definite direct object marker

Questions & Answers about این دانشمند فرانسوی بود که میکروب را کشف کرد.

Why does the sentence start with in (this) instead of a word for 'it'?

In Farsi cleft sentences, which focus on a specific piece of information, we use in to say 'It is' or 'It was'. The structure in ... bud ke literally means 'This ... was that', but it is the standard way to express 'It was ... who/that' in English.

Can I use ki (who) instead of ke since we are talking about a scientist?

No, you must use ke. In Farsi, ke is the universal linking word for these focus structures. While English switches to 'who' for people, Farsi always uses ke to connect the focused subject to the rest of the sentence.

Why is the object marker ra used after mikrob here?

The word mikrob is the direct object of the verb kashf kard (discovered). By adding ra, the sentence treats 'the microbe' as a specific, defined scientific concept that was discovered, matching the English translation 'the microbe'.

Could ra be placed after kashf instead of mikrob?

No, because kashf kard is a compound verb that works together to mean 'discovered'. The object being discovered is the microbe, so the object marker ra must attach to mikrob, not jump inside the two parts of the compound verb.