阅读下面短文，根据以下提示：1)汉语提示，2)首字母提示，3)语境提示，在每个空格内填入一个适当的英语单词，所填单词要求意义准确，拼写正确，并将该词完整地写在答题卡中相应的横线上。
A recent study suggests that students who bring water into exams may improve their grades by 10 percent．
Scientists then____(比较) their exam results with their normal schoolwork grades．They found that all those ______had brought drinks with them got better grades．
Scientists also considered the students 'schoolwork and_____(预计)their grades．This was to make sure that the reason was not simply that smarter students were more________(有可能)to bring drinks with them．
______is unclear why drinking water improves exam results．But scientists say having enough water in ourb      and not feeling thirsty could have a helpful effect ________our brains．Drinking water may also cutd_____ on anxiety ,which affects exam performances．
So next time，w    you are going to have a big exam，try bringing a bottle of water with you．Who knows—it may help youp     the exam!