Parts of the body

Names of parts of the body, like 'hand', 'face', and 'knee', are usually count nouns used with the indefinite or definite article according to the standard rules of use (see Chapters 3 and 4).We have also seen a special use of the definite article to refer generically to body parts (Chapter 5). There is also a use where we are thinking of parts of the body not as separate organs or limbs but as locations on the body. For this you can use the definite article.

They might dash out later and stab them in the back.

She had the urge to beat him over the head.

It is possible to use the definite article with a singular noun even when there are two possible parts.

Sam took John by the arm.

It bit her on the leg.

He was wounded in the leg too.

Here there is no suggestion that John has only one arm (mentioned before) or that 'he' has only one leg; the part of the body is all that is important, not which side.

You use the definite article like this when the noun referring to the body part is included in a prepositional phrase ('in the back', 'by the arm') after a verb of touching or injuring ('shake', 'bite'), and the person whose body you are referring to has just been mentioned ('them', 'John').

When the noun comes straight after a verb such as 'grab' or after a verb and a preposition, for example 'step on', you have to use a possessive determiner like 'their' or 'his'; for example, you have to say 'I stepped on his foot' not 'I stepped on the foot'. Sometimes there are alternatives: 'I shook him by the hand' or 'I shook his hand'.

The black-haired youth grabbed her arm and shook her.

Robert touched her cheek.

You can also use the definite article when referring to a touch, blow, or pain.

...giving me a friendly pat on the shoulder.

I have a pain in the side.