Learn Hardcore Turkish: Minibüs yerine tramvayı tercih etmek genellikle daha hızlıdır. - Choosing the tram instead of the minibus is generally faster.

Because tercih etmek is a transitive verb that takes its direct object in the accusative. Adding -ı (becoming tramvayı) marks tramvay as the specific thing being preferred: “(to prefer) the tram.”

Why isn't there a genitive ending on minibüs before yerine?

yerine is a postposition meaning instead of. Formally you could say minibüsün yerine, where -ün is the genitive marker. However, in everyday Turkish it’s very common (and perfectly acceptable) to drop the genitive and simply say minibüs yerine.

What is the function of the phrase Minibüs yerine tramvayı tercih etmek in the sentence?

That entire chunk is a verbal noun (an infinitive phrase) acting as the subject. It literally means “Choosing the tram instead of the minibus.” Turkish often uses such nominalized clauses as subjects without any extra particles.

What part of speech is genellikle, and why is it placed before the predicate?

genellikle is an adverb meaning “generally” or “usually.” In Turkish, adverbs typically appear close to the verb or predicate they modify. Here it qualifies the whole statement and sits just before the predicate daha hızlıdır.

Why does the sentence end with daha hızlıdır instead of just daha hızlı?

To say “is faster,” you need two things:

daha makes the adjective comparative (more fast = faster).
-dır is the third-person singular copula, turning daha hızlı into a full predicate: daha hızlıdır = “(it) is faster.” In casual speech you might hear daha hızlı alone, but the suffix is standard in writing.

What does the suffix -dır in hızlıdır indicate?

-dır is the Turkish copula for third-person singular, used with adjectives or nouns to mean “it is” or “this is.” In hızlıdır it completes the predicate: hızlı (“fast”) + -dır = “is fast” (here in comparative form, “is faster”).

Why is there no explicit subject pronoun in this sentence?

The subject is already the nominalized action Minibüs yerine tramvayı tercih etmek. Since that clause clearly functions as the subject, Turkish omits any extra pronoun. The verb form -dır agrees with a third-person subject implicitly.

What word order does this sentence illustrate?

Turkish typically follows Subject–Object–Verb (or subject–predicate-final) order. Here you see:

Subject (the nominalized clause)
Adverb (genellikle)
Predicate (daha hızlıdır)