- Parents shouldn't _______ stay out late at night before schooldays.   let their children

- Piaget described four stages of cognitive development _______ .   and related them to a person's ability to understand and assimilate new information

- Please speak a little _______.   louder.

- Please speak a little more _______.   slowly

- Principals _______ to be ashamed if they cannot communicate in English with foreign students and their parents.   ought

- Problems related to immigration are getting _______ .   more and more complex

- Progress towards the Lisbon objectives in education is going through a _______ time.   challenging