1.老师们常劝说我们上课要集中注意力。 Our teachers often persuade us to _concentrate on____ _____ the lessons in class. 2.吉米是以为非常了解学生饭菜情况的厨师。 Jamie is a cook who knows a lot about what the students' meals __should be___ _____. 3.They can't _concentrate____ (集中精力) on their study.(填一个单词)