Full Idea
For Frege, expressions always contribute ways of thinking of their referents, rather than the referents themselves, to the thoughts expressed by sentences.
Gist of Idea
Expressions always give ways of thinking of referents, rather than the referents themselves
Source
report of Gottlob Frege (On Sense and Reference [1892]) by Scott Soames - Philosophy of Language 1.16
Book Reference
Soames,Scott: 'Philosophy of Language' [Princeton 2010], p.17
A Reaction
I have some sympathy for Frege. It always strikes me as daft to think that if I say 'my dustbin is empty', the dustbin becomes 'part' of my sentence. Sentences don't contain large plastic objects.