officially there is no 1/2 day government subsidized nursery but you may call them and ask. Some will accept 1/2 day 1/2 price. Or you may attend the hourly count attendence which is designed for occasional nursery care. Its super cheap!!
CHKWAN : I meant you may check for 1/2 day attendence ( with 1/2 price ) from government subsidized day nursery. But it depends on the policy of the nursery. You have to call up one by one to check possibility! But by this way you cannot apply for the school fee reduction from social service dept.