Luckily for us, the train was late.
我们真凑巧，火车晚点了。
The accident could have been much worse; luckily no harm was done.
这次事故本来可能糟糕得多；所幸没有造成伤害。
Luckily I was feeling in a good mood.
幸好我当时情绪好。
Luckily, a bush broke his fall.
幸亏有灌木接着，他摔得不重。
Luckily, I am a good swimmer.
幸好我是个游泳好手。