This paper argues that the verb help has the function of a semi-auxiliary. When the verb help is followed by an infinitive, it appears in four sentence types, as shown in (i)-(iv) below.
(i) John helped Mary to wash the dishes.
(ii) John helped Mary wash the dishes.
(iii) John helped to wash the dishes.
(iv) John helped wash the dishes. In the types (iii) and (iv), we sometimes find a sentence in which the subject of help is identical with the implicit infinitival subject not only in Present-day but also in earlier English. This usage of help satisfies Kajita's (1968) defining characteristics of a semi-auxiliary. In the sentence where help has developed the function of a semi-auxiliary, it is suggested that the central meaning of help ‘to aid, to assist’ has changed to the marginal meaning ‘to serve’.
