He is (suitable) to be a doctor.
He is (appropriate) to be a doctor.
He is (competent) to be a doctor.
He is (qualified) to be a doctor.
任选,供参；优先推荐前2我才上初一不懂你那么多，我有点不确定，不然又要三点一线那就He is (fit) to be a doctor.be fit to do，适合做...，能胜任做...fit应符合初一词汇量