要是我多懂得一些急救知识，我就能帮助他们了。

If I had known more about first aid, I would have helped them.

youdao

要是我多懂得一些急救知识，我就能帮助他们了。

If have had known more about first aid, I could help them.

youdao

要是我多懂得一些急救知识，我就能帮助他们了。

If have had known more about first aid, I could help them.

youdao