子供達が

the children

→ 子供
phrase Common #5,115
the children 子供達 means “children,” and が marks them as the subject of the sentence. 子供たち and 子どもたち are common alternative spellings.
JA: 子供達が公園で遊んでいます。
EN: The children are playing in the park.

彼女は子供達が東京に行ってしまったので、とてもさみしい思いいる

She feels very lonely because her children have gone to Tokyo.

私は子供達が歩いて道を横断するのを見た

I saw the children walk across the street.

子供達が可哀想

I feel sorry for the children.

— コーラス (2004)

他の子供達が笑いました

The other children laughed.

子供達が私の言うことを理解できるようにゆっくり話した

I spoke slowly so that the children could understand what I was saying.

トムの前で子供達が座っていた

The children were sitting on the floor in front of Tom.

子供達が一列並んでバスを待つ

The children line up in a row and wait for the bus.

ここでは子供達が安心して遊べる

Children can play here safely.