Learn Hardcore Turkish: Su kupaya aktarılmalı. - Water should be transferred to the cup.

aktarılmalı comes from the verb root aktar- (“to transfer”). First you add the passive suffix -ıl (vowel-harmonized to -ıl):
aktar- + -ıl → aktarıl- (“be transferred”)
Then you add the necessity suffix -malı to express obligation:
aktarıl- + -malı → aktarılmalı (“must be transferred”).

What is the difference between aktarmalı and aktarılmalı?

• aktarmalı = root aktar- + necessity -malı → active meaning “he/she/one must transfer (it)”.
• aktarılmalı = root aktar- + passive -ıl + necessity -malı → passive meaning “it must be transferred” (without specifying who does it).

Why isn’t su marked with the accusative -yu (as in suyu)?

In Turkish, when you turn an active sentence into passive, the original object becomes the new subject and takes the nominative (unmarked) form. That’s why we have su (not suyu) before the passive verb.

What case is kupaya, and how is it formed?

kupaya is the dative case, meaning “to the cup.” The dative suffix is -a/-e (chosen by vowel harmony). Because kupa ends in a vowel, you insert a buffer consonant y before the suffix:
kupa + y + a → kupaya.

Why do we need a buffer consonant y in kupaya?

Turkish generally avoids two vowels in a row. When a noun ends in a vowel and you add a vowel-initial suffix, you insert a buffer consonant (y or sometimes n) to prevent vowel hiatus. Hence kupa + a becomes kupaya.

Why is there no explicit subject in Su kupaya aktarılmalı?

Passive sentences in Turkish often omit the agent (the “doer” of the action) when it’s unknown, unimportant, or obvious from context. The focus is on the action itself (“must be transferred”), not on who does it.

What is the word order in this sentence, and how does it fit typical Turkish structure?

Turkish is a Subject-Object-Verb (SOV) language. In passive sentences the old object becomes the new subject (here su), then you have any adverbials or case-marked phrases (here kupaya “to the cup”), and finally the verb (aktarılmalı). So it follows the standard SOV pattern with no visible agent.

How else can you express “must be transferred” besides the -malı suffix?

You can use gerekmek or zorunda olmak:
• Su kupaya aktarılması gerekiyor. (nominalized passive + gerekiyor)
• Su kupaya aktarılmak zorunda. (nominalized passive + zorunda olmak)
Both mean roughly “The water needs to be transferred to the cup.”