He trudged home feeling lonely and let down.
他步履艰难地往家走，感到孤独而沮丧。
She felt lonely and hopeless.
她感到孤独绝望。
I don't get lonely now because I make the effort to see people.
我现在不觉得孤独了，因为我尝试着与人交往。
They often have a lonely and solitary life to lead.
他们常常过一种独居的孤独生活。
I would imagine she's quite lonely living on her own.
我猜想她一个人过肯定很孤独。