Page 1 of 2 1 2 Last
Results 1 to 10 of 17

Thread: skid marks

  1. Key Member
    Student or Learner
    • Member Info
      • Native Language:
      • Turkish
      • Home Country:
      • Turkey
      • Current Location:
      • Turkey

    • Join Date: Jun 2016
    • Posts: 2,087
    #1

    skid marks

    Original: How can we use the skid marks of a car to estimate the car's speed before the brakes were applied."

    I think instead of simple past the use of "present perfect" would be better. So what do you think?

    Mine try: How can we use the skid marks of a car to estimate the car's speed before the brakes have been applied."

    Source: Algebra & Trigonometry by Keedy/Bittinger.

    Thank you.

  2. VIP Member
    Interested in Language
    • Member Info
      • Native Language:
      • American English
      • Home Country:
      • United States
      • Current Location:
      • United States

    • Join Date: Dec 2015
    • Posts: 14,736
    #2

    Re: present perfect passive v. simple past passive.

    The original is logical: we are now estimating the speed of the car at the time in the past when the brakes were applied.

    The present perfect version is not logical. It says that, at a time before the brakes were applied, we will use skid marks that cannot yet exist to estimate the car's speed.
    I am not a teacher.

  3. VIP Member
    Retired English Teacher
    • Member Info
      • Native Language:
      • British English
      • Home Country:
      • Europe
      • Current Location:
      • Czech Republic

    • Join Date: Jul 2015
    • Posts: 15,472
    #3

    Re: present perfect passive v. simple past passive.

    Quote Originally Posted by hhtt21 View Post
    Mine try
    My try

  4. Key Member
    Student or Learner
    • Member Info
      • Native Language:
      • Turkish
      • Home Country:
      • Turkey
      • Current Location:
      • Turkey

    • Join Date: Jun 2016
    • Posts: 2,087
    #4

    Re: present perfect passive v. simple past passive.

    Quote Originally Posted by GoesStation View Post
    The original is logical: we are now estimating the speed of the car at the time in the past when the brakes were applied.

    The present perfect version is not logical. It says that, at a time before the brakes were applied, we will use skid marks that cannot yet exist to estimate the car's speed.
    Two two versions seems to me in meaning what you have explained here. It seems to me that the time adverb, before, implies this. So shouldn't it be "after" instead of "before" in two versions?

    So I would like to ask what is the difference between

    1.we are now estimating the speed of the car at the time in the past before the brakes were applied.
    2.we are now estimating the speed of the car at the time in the past after the brakes were applied.
    Last edited by hhtt21; 04-May-2017 at 11:08.

  5. Moderator
    Retired English Teacher
    • Member Info
      • Native Language:
      • English
      • Home Country:
      • England
      • Current Location:
      • England

    • Join Date: Jun 2010
    • Posts: 28,595
    #5

    Re: present perfect passive v. simple past passive.

    Please note that I've changed your thread title.

    Isn't that more eye-catching?

  6. VIP Member
    Interested in Language
    • Member Info
      • Native Language:
      • American English
      • Home Country:
      • United States
      • Current Location:
      • United States

    • Join Date: Dec 2015
    • Posts: 14,736
    #6

    Re: present perfect passive v. simple past passive.

    There's no reason to change the original sentence.
    I am not a teacher.

  7. Key Member
    Student or Learner
    • Member Info
      • Native Language:
      • Turkish
      • Home Country:
      • Turkey
      • Current Location:
      • Turkey

    • Join Date: Jun 2016
    • Posts: 2,087
    #7

    Re: present perfect passive v. simple past passive.

    But in both cases ie the present perfect or past simple, we are searching for the speed, the maximum speed just before the brakes. The brakes are applied. At that time, both brakes are applied and the car has its maximum speed and this is the time the skid marks beginning to form. What is wrong with this explanation?

    Thank you.

  8. VIP Member
    Interested in Language
    • Member Info
      • Native Language:
      • American English
      • Home Country:
      • United States
      • Current Location:
      • United States

    • Join Date: Dec 2015
    • Posts: 14,736
    #8

    Re: present perfect passive v. simple past passive.

    Quote Originally Posted by hhtt21 View Post
    Original: How can we use the skid marks of a car to estimate the car's speed before the brakes were applied."

    <snip>

    How can we use the skid marks of a car to estimate the car's speed before the brakes have been applied."
    Quote Originally Posted by hhtt21 View Post
    But in both cases ie the present perfect or past simple, we are searching for the speed, the maximum speed just before the brakes. The brakes are applied. At that time, both brakes are applied and the car has its maximum speed and this is the time the skid marks beginning to form. What is wrong with this explanation?
    Your version is illogical. The car will produce skid marks after the brakes are applied. Since the skid marks are not there yet, you can't use them to estimate anything before the brakes have been applied.
    I am not a teacher.

  9. Key Member
    Student or Learner
    • Member Info
      • Native Language:
      • Turkish
      • Home Country:
      • Turkey
      • Current Location:
      • Turkey

    • Join Date: Jun 2016
    • Posts: 2,087
    #9

    Re: present perfect passive v. simple past passive.

    Quote Originally Posted by GoesStation View Post
    Your version is illogical. The car will produce skid marks after the brakes are applied. Since the skid marks are not there yet, you can't use them to estimate anything before the brakes have been applied.
    If "before the brakes have been applied" is used the marks do not appear but if "before the brakes were applied" is used the marks appear. This is the point I cannot distinguish the difference and I do not know how I will distinguish. I cannot distinguish how this two tenses introduce very different situations.

    So, would you please try to explain this "distinguishing point" in a different way?

    Thank you.

  10. VIP Member
    Interested in Language
    • Member Info
      • Native Language:
      • American English
      • Home Country:
      • United States
      • Current Location:
      • United States

    • Join Date: Dec 2015
    • Posts: 14,736
    #10

    Re: present perfect passive v. simple past passive.

    I understand your confusion. I hope one of our actual teachers can jump in here to explain this. I'm sorry, but I don't know how.
    I am not a teacher.

Page 1 of 2 1 2 Last

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •