請問Smiling helps keep your heart healthy,這句話中helps keep 詞性如何分析,謝謝?

help 當動詞用時，是協助的意思。其後面可接to，也可省略。 Smiling helps (to)keep your heart healthy,句型是S+V+O，不定詞片語to keep your heart healthy，所以文法分析時to需還原

modal --adj. relating to mode , manner which is contrasted with substance. In grammar it is the mood of a verb.
modal auxiliaries are eg:-can, may, could, should, would etc.where 11 modal  auxiliaries are found that help add to the meaning of the main verbs.
modality is the state of being modal, the way in which something is done.
(1) Verb Group:-Auxiliary:-Have been helping
modal:-should keep;
(2)Auxiliary (to) modal:-
Have to keep
(3)phrase modal:-Have to be; hence "Have to be or have not to be where no "human items" can be added."
Have to help---> (3) + (2)----> Have to help + Have to keep--->help to keep---->hence to analyse the sentence "to" must be added  resume in order to learn what it is made up of.
We can find modal phrase =help keep;
Hence help keep your heart healthy by smiling.
Hence:-Smiling help keep your heart healthy.