asked that Jack turn off heating vs. asked that Jack turns off heating

[GoodTaste]

1) Mary has asked that Jack turn the heating off before leaving the house.
2) Mary has asked that Jack turns the heating off before leaving the house.

Which sentence is correct in using the form of verb "turn"?

 

[Charlie Bernstein]

1) Mary has asked that Jack turn the heat off before leaving the house.

[STRIKE]2) Mary has asked that Jack turns the heating off before leaving the house.[/STRIKE]

Which sentence is correctly using a form of the verb "turn"?

Use #1, "turn."

Use "heat," not "heating."

And did she ask him to turn it off or turn it down? Down seems more likely.

More natural: Mary asked Jack to turn the heat down before leaving the house.

 

[GoodTaste]

What I don't really understand is that "that" marks the beginning of a clause which entitles the verb to be consistent with the subject in it (so "that Jack turns the heat off" appears to be grammatical for Jack is singular). But "asked that Jack turn the heat off" is idiomatic.

 

[5jj]

1) Mary has asked that Jack turn the heating off before leaving the house.
2) Mary has asked that Jack turns the heating off before leaving the house.

Which sentence is correct in using the form of verb "turn"?

'Turn' is correct grammatically. It is the subjunctive form required in ask that someone do something. You won't hear it much; most people would say Mary has asked Jack to turn the heating off/down before leaving the house.