He is at least as tall as his brother,  if not_______ ．

—I watch I Am a Singer every Friday night.—Me too. I have never seen a ________ entertainment program.

In the middle of the room there is a ______ table, with eight chairs around it.

When dealing with students, teachers are supposed to adopt ______ and caring approaches, as they are unique young individuals of different personalities. 

 The loss of ability in the mother tongue is mainly caused by the         use of electronic devices and a lack of attention to culture.