来自李大勇的问题
【wemustmakea_____(care)studyoftheproblem】
wemustmakea_____(care)studyoftheproblem


【wemustmakea_____(care)studyoftheproblem】
wemustmakea_____(care)studyoftheproblem
wemustmakeacareful(care)studyoftheproblem