Learn Turkish: Bu toksik duman, çocukların öksürüğünü tetikler. - This toxic smoke triggers the children's cough.

Yes! Tetiklemek (to trigger) is a direct verb that takes the accusative case (öksürüğünü). If you wanted to use the lesson's target grammar, you would change the noun "cough" into an action using the factive -mAsI structure and add the dative case: Bu toksik duman, çocukların öksürmesine sebep olur. (This toxic smoke causes the children to cough).

Let's break down öksürüğünü. Why are there two -ü endings here?

The base word is öksürük (cough). The first -ü is the third-person possessive suffix linked to çocukların (the children's cough), which causes the final -k to soften to -ğ. The second -ü is the accusative case marker, needed because the cough is the specific direct object being triggered. The -n- in the middle is a buffer letter, which is always required when attaching a case marker to a third-person possessive suffix.

Since çocukların is plural, why doesn't the sentence use the plural possessive öksürüklerini (their coughs)?

In Turkish, when a plural subject shares a general condition, state, or a single type of object, it is very common to use the singular possessive (here, öksürüğü). Saying öksürüklerini wouldn't be wrong, but the singular emphasizes the general condition of coughing rather than treating them as multiple individual, countable coughs.