Which statement is not correct with reference to primary auxiliaries?
1
Primary auxiliaries 'do' can function as a main verb meaning 'to perform' or 'to complete'.
2
In negative sentences, the 'not' is usually placed immediately after the primary auxiliary.
3
Primary auxiliaries always carry the main stress in a sentence.
4
The contracted forms ('m, 's, 're, 've, 'd) are contractions of primary auxiliaries.