Should the noun position be singular or plural in the following sentence?
You should focus on the position(s) of your lips and tongue pronouncing this sound.
Should the noun position be singular or plural in the following sentence?
You should focus on the position(s) of your lips and tongue pronouncing this sound.
Singular.
This is a counter-intuitive, but although you are talking about two [or even three!] things (lips and tongue), you could well choose to use the singular because position means "the placement [of what is being considered] relative to other things", and so can be used to describe the situation as a whole: each thing/assemblage can only have one position at a time. This applies even if you're talking about a set-up involving lots of different things, eg
"The position/s of the chess pieces on the board".
You would be forced to use the plural in cases where the thing or set-up you are discussing changes its position over time and you are bringing this point out, for example:
"Throughout the pronunciation exercise you will move your lips and tongue into lots of different positions, some of which might feel unusual."