ANSWERS TO INTRODUCTORY WORD GROUPS EXERCISE:

1. Since Pete was always online playing computer games,  Andy decided to buy his own computer.  

      Because this sentence starts with "since," you know that you have an introductory word group, and a comma therefore needs to be placed somewhere in the sentence.

      2.      Convinced that she would need extra money for college,  Andrea applied for a second job at the library. (correct)

    3.      In fact, most students find it hard to sleep past six-o’clock a.m. during the semester, so you may as well take 8:00 classes.  

"In fact" is an introductory word group; you can hear a natural pause when you read it out loud.

    4.      When you write an argumentative essay, you should make sure to consider how your readers will respond. (correct)

    5.      Once you have formulated a tentative thesis, you will be ready to begin doing research.  

"Once you have formulated a tentative thesis" is an introductory word group, which introduces the main part of the sentence--when will you be ready to do research?

6. If you want to succeed in your first semester, you need to make sure to give yourself adequate time to study. 
(correct)

      7.      Frightened, we backed into the driveway without a sound.  
  (correct)

      8.      Because Joanne wanted to graduate by 2003, she decided to take 21 hours in the spring semester.  (correct)