ここにいれば

if (someone) is here

→ 此処
phrase Rare #32,135
if (someone) is here The conditional form of ここにいる, meaning “to be here.” Depending on context, it can also mean “if (someone) stays here.” With のに, it often expresses a wish or regret, such as “if only they were here.”
JA: あなたがここにいれば、もっと安心できる。
EN: If you were here, I would feel much more at ease.

ここにいればよかったのに

You should have stayed here.

彼女がここにいれば何をすべきか教えてくれるだろうに

If only she were here, she could tell us what to do.

テッドここにいれば彼は私たちの部屋をきれいにするの手伝ってくれるのに

If Ted were here, he would help us clean our room.

何年もここにいれば肉体は-意のままに動きます

After being here for years, your body moves exactly as you want it to.

— Carandiru (2003)

ここにいれば安全だ

It's safe here.

— クワイエット・プレイス (2018)

もし僕の兄さんここにいればどうすればいいわかるだろう

If my older brother were here, he’d know what to do.