好在 (hǎo zài): luckily; fortunately

I forgot to bring an umbrella, but luckily there was a disposable raincoat in my bag, so I didn't get wet.

Yesterday I got lost and my phone was dead, but luckily I met a kind old lady who walked me to the subway station.

This exam was very difficult, and I couldn't do many questions, but luckily I had reviewed the key chapters and barely passed.

While we were climbing the mountain, it suddenly started raining heavily, but luckily there was a small pavilion nearby, and everyone quickly ran inside to shelter from the rain.

I was worried about missing the train, but luckily the taxi driver drove very fast, and I arrived at the station ten minutes early.