probably /ˈprɑb.ə.bli/ /ˈprɒbəbli/
perhaps /pərˈhæps/ /pəˈhæps/
possibly /ˈpɑs.ə.bli/ /ˈpɒsəbli/
presumably /prəˈzuməbli/ /prɪˈzjuːməbli/