# Is "how long is the average time your sketches take to finish?" a correct sentence?

I want to ask someone about the normal/average time she needs to finish a sketch/drawing.

I have several options of question and I feel there should be some corrections to these question sentences. I'm also still confused on how to use "how" and "what" in these questions. Are they both acceptable? Any help would be appreciated.

1. How long is the average time you need to finish a sketch?
2. What is the average time you need to finish a sketch?
3. How long is the average time your sketches take to finish?
4. What is the average time your sketches take to finish?

2 and 4 are correct. 1 and 3 are incorrect.

Native English speakers use "what" when asking about time, distance, weight, etc, but not "how ___".

Incorrect:

How long is the time...? How much is the weight...? How far is the distance...?

Correct:

What is the time...? What is the weight...? What is the distance...?

Correct:

How long is it...? How long does it take...? How heavy is it? How much does it weigh? How far is it...?

• I was just thinking so, but I wanted to construct a sentence that would accommodate the "average time" in it. Commented Mar 6, 2017 at 16:23
• Adding a modifier like "average" shouldn't change the grammar of the basic sentence. "What is the average time/weight/distance...?" is okay, but not "how much is the average time/weight/distance...?" Commented Mar 6, 2017 at 16:44
• I agree with the answer and would add another observation. "The average time" already specifies what you're looking for. "How long is" is redundant and doesn't really make sense. Similarly, you wouldn't ask "How long is the length of,,,". You would just ask, "What is the length of...". Commented Mar 6, 2017 at 17:01
• +1 for "How long does it take to finish a sketch?" – which I think is the best way to phase this.
– J.R.
Commented Mar 7, 2017 at 1:29

A clearer way to ask the question would be "On average, how long does it take for you to finish a sketch?" If you want to ask it with more sympathy towards this person (especially if you are asking a friend about a potential deadline), you can replace "how long does it take" with "how much time do you need."

LucasGabriel posed the question, 'to want to ask someone about the ... time she needs to finish'. So, the question is asking her to consider work performed in the future, "How long would you expect to take to sketch a car next week?" or "How long would it take you to sketch a car next week?". In contrast, if the question were asking her to consider previous work, "How long did it take you to sketch that car?" Here 'did' is used to change the tense of 'take'.