小题1:are well worth reading
小题2:had been on the phone for
小题3:marked the success of the experiment
小题4:are not allowed to swim alone/ on their own/ by themselves
小题5:The novel written by a new writer
小题6:expensive that few people can afford it / to buy it
小题1:很值得be well worth doing， those magazines做主语，故用are well worth reading.
小题2:had been on the phone for 打电话on the phone for＋一段时间。
小题3:．．．的成功，要用the success of 故用，marked the success of the experiment
小题4:be not allowed to do sth．不被允许做某事， on one’s own独自。
小题5:一个新作家写的小说，过去分词做后置定语，表被动，故用，The novel written by a new writer
小题6:so…that…如此……以至于;afford 支付得起．故用，expensive that few people
can afford it / to buy it