How many morphemes are there in the sentence "i wanted it"?

The sentence 'I wanted it' has four morphemes. Morpheme is defined as a meaningful morphological unit of a language that can not be further divided; it is the smallest meaningful unit of a language. A morpheme may or may not stand alone. A morpheme that is standing alone is called root while that that can not stand alone is called 'affix'. Every word is made up of one or more morphemes. The morphemes in the sentence given above are: I, want, ed, it. 

Bis correct.