Magnae says hello to everyone

I am Magnae and now I’m preparing for the Toeic exam and I find this site really interesting and helpful.
Hope everyone can help me with any of these questions.

  1. The amounts of oxygen and nitrogen in the air almost always remain stable”
    Is “the amounts” correct? What is the difference if we use “the amount” instead?
  2. “Multicolored woodcuts must be printed with as many blocks as there are_____ colors in the composition”
    Could you explain the usage of “there are” here?
  3. While ancient times people simply painted inanimate objects, during the Renaissance the painting of still-life developed as an accepted art form”.
    Why is “while ancient” wrong? (according to the answer key)
  4. “A dolphin locates underwater objects in its path by doing a series of clicking and whistle sounds.”
    “to object” here means to shape like a particular object, am I right?
    Many thanks,
    Have a nice day,
    Magnae.

Hi

‘Amounts’ or’ amount’ can be used with 1. ‘Amounts’ treats the two gases separately, whilst ‘amount’ combines them both.

  1. The same amount of blocks as colours. For each colour there has to be a new block.

  2. It needs a preposition.
    Whilein ancient times…

  3. ‘Objects’ here simply refers to a material thing that can be seen and touched.

Now I can deal with them,
Thanks so much, teacher.