—You don’t seem to be quite yourself today. What’s wrong? —Oh, I’m suffering from a cold. Nothing serious, _____. 

He could have finished it on schedule, but ________ he fell behind.

After searching for several hours, the boy was _____ too pleased to find his lost mobile phone.

If you smoke a cigarette every day, you will _____ become addicted to smoking．

When we think of communication , we _________ think of using words---- talking face to face, writing messages, and so on .