only: focusing adverbial
Only can be used as a focusing adverbial (see here). It can refer to different parts of a sentence.
Referring to the subject
Only normally comes before a subject that it refers to.
- Only you could do a thing like that.
- Only my mother really understands me.
Referring to other parts of a sentence
When only refers to another part of a sentence, it often goes in ‘mid-position’ with the verb (see here) for details).
- She only reads biographies.
- I only like swimming in the sea.
- She is only on duty on Tuesdays.
- I’ve only been to India once.
- She was only talking like that because she was nervous.
Ambiguous sentences
Sometimes sentences with only are ambiguous (they can be understood in more than one way).
- I only kissed your sister last night. (The sense can be ‘only kissed’, ‘only your sister’ or ‘only last night’.)
In speech, the meaning is usually clear because the speaker stresses the part of the sentence that only refers to. Even in writing, the context generally stops sentences like these from being really ambiguous. However, if necessary only can be put directly before the object, complement or adverbial expression that it refers to. This is generally rather formal. Compare:
- They only play poker on Saturday nights. (could be ambiguous)
- They play only poker on Saturday nights.
- They play poker only on Saturday nights.
The meaning can also be made more precise with a relative structure.
- Poker is the only game (that) they play on Saturday nights.
- Saturday nights are the only time (that) they play poker.
only today, etc
Only with a time expression can mean ‘as recently as’ or ‘not before’.
- I saw her only today – she looks much better.
- Only then did she realise what she had agreed to.
- My shoes will only be ready on Friday.
For inverted word order after only, as in the last example but one, (see here).
Only can also be a determiner in a noun phrase (e.g. You are my only real friend).