夜晚，我望着浩瀚的天空，仿佛亲身游历了敦煌的历史，感受到千年敦煌历史的沧海桑田。
B-Time I-Time O B-Person O O O O O B-Thing I-Thing O O O O O O O O B-Location I-Location O O O O O O O O O B-Location I-Location O O O B-Thing I-Thing I-Thing I-Thing O