点击下方单词,选择对的这个单词
形容词
1. 未必的;不大可能的If it is doubtful that something will happen, it seems unlikely to happen or you are uncertain whether it will happen.
2. 怀疑的;疑惑的;拿不定主意的If you are doubtful about something, you feel unsure or uncertain about it.
多通过句子记忆单词,而不是单独死记硬背。