O aniden ağlamaya başladı, ben onu sakinleştirip su verdim.

the water

Breakdown of O aniden ağlamaya başladı, ben onu sakinleştirip su verdim.

• ben: I
• ağlamak: to cry
• o: she

Questions & Answers about O aniden ağlamaya başladı, ben onu sakinleştirip su verdim.

Why is it "ağlamaya başladı" and not "ağlamayı başladı" or just "ağlama başladı"?

With verbs, başlamak takes the verbal noun in the dative: -mA(y)a. So the correct pattern is: verb stem + -mA + -(y)a → ağla-mA-ya başladı.

• ağlamayı başladı is wrong with başlamak.
• ağlama başladı is grammatical but different: it means “the crying started” (treating ağlama as a noun), not “he/she started to cry.”

What does the -ip in "sakinleştirip" do?

The suffix -ip is a converb that links two actions with the same subject and tense: “X and (then) Y.” So sakinleştirip su verdim = “I calmed [him/her] down and (then) gave [some] water.” You could also say “sakinleştirdim ve su verdim,” but -ip is more compact and suggests sequence.

Why is it "onu" (accusative) before "sakinleştirip," not "ona" (dative)?

Because sakinleştirmek (“to calm someone down”) is a transitive verb that takes a direct object in the accusative: onu. The dative ona would be used with verbs that take an indirect object (e.g., yardım etmek “to help [someone]”).

Should it be "ona su verdim" instead of just "su verdim"?

If you want to specify the recipient, yes: ona su verdim (“I gave water to him/her”). The sentence as written is natural in conversation (the recipient is recoverable from context), but the most explicit version is: Onu sakinleştirip ona su verdim.