(1) A person guilty of an offence under section 6(1)(a) is liable on conviction to be punished according to the gravity of the offence as follows:

(a) to the sentence of imprisonment fixed by law, if the corresponding offence specified in Schedule 2 is one for which the sentence is fixed by law;

(b) to imprisonment for life, if the corresponding offence specified in Schedule 2 is one for which the maximum sentence is imprisonment for life;

(c) to imprisonment for a term not exceeding 2 years more than the maximum term of imprisonment for the corresponding offence specified in Schedule 2, if that corresponding offence is one for which a person of full capacity and not previously convicted may be sentenced to a maximum term of 10 or more years of imprisonment;

(d) to imprisonment for a term not exceeding 1 year more than the maximum term of imprisonment for the corresponding offence specified in Schedule 2, if that corresponding offence is one for which a person of full capacity and not previously convicted may be sentenced to a maximum term of less than 10 years of imprisonment,