exercise on p. 15 of textbook Modal verbs (情态动词) , hedges (模糊限定词) and some sentence patterns could help to make sentences tentative . e.g. It might be the case that herbs in the paper-making materials result in high-quality paper-making. It is likely that some virus has no effect on animals but will be fatal to human beings. Task D on p. 15 Rewrite following sentences to make them suitable for the requirements in brackets. 1 There is no doubt that most students need to improve their standard of English. (less likelihood) 2 Students who adopt a good approach to learning will be successful in university. (likelihood) 3 Students will improve their language skills by only doing written exercises. (doubt) 4 Students who study in groups experience the greatest success. (less likelihood) 5 Teachers who are punctual receive the best feedback from students. (likelihood)