Fill in each of the blanks in the following sentences with a suitable preposition or adverb. (用适当的介词或副词填空) 1. Unfortunately, the hat I had just bought was no longer fashion. 2. You ought to pay more attention the quality of these goods. 3. I want to complain the food and the service in this restaurant. 4. There is a trend a more natural look at the moment. 5. We have invited an expert this area to give us a speech. 6. I have a strong desire fresh air after staying in the small room for several hours.