All of us are_____aware of the cause of this failure, so do not make the same mistake again.

—— How ＿＿＿＿＿＿＿＿ can you finish the drawing? —— In a week. 

 When you feel you are happier and more relaxed after having a cigarette, you may become ________addicted.

However weak we are，we can still do something against the powerful nature so long as we are     prepared．

 He was the last man I wanted to meet, but I      managed to smile at him.