Diagram the simple subject and the simple predicate of each sentence.

1.Where do people use machines? people/use

2. Machines exist in homes, office buildings, and hospitals. Machines/exist

3. What amazing things machines can do! Machines/can do

4. Listen

6 answers

2 and 3 are correct.

There's an auxiliary (helping) verb in #1. do you see it?

For #4, if that's all there is to the sentence, then the subject is "the understood 'you'" --
http://members.cox.net/teachro/diagramming/nounsverbs/youunder.htm
from http://members.cox.net/teachro/
4. Listen to the radio. You/listen

5. Some machines perform several tasks. Machines/perform

6. Do you use a computer? you/use

7. Try this program. You/try

8. What a fast printer you have! You/have

9. How long does it take. it/take

10. This printer works beutifully. printer/works
for #1 is it people/do use
Yes, now you have #1 correctly done.

For #s 4 and 7, put the word "you" in parentheses. For example, (you)/listen

Re-think #s 6 and 9 in light of #1.

The rest are fine.
thanks
yup
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