It's the customary bedtime practice every parent would feel fearful----being asked to read the same book for many times．But while the （41）___ repetition might be boring for mum or dad，it is the best way for toddlers to learn new words，according to research．

The findings suggest parents are wasting money by spending a fortune on huge book collections in the hope they will inspire their little ones．Instead，a small selection of favourites such as The Very Hungry Caterpillar or The Gruffalo will（42）___ far more．

Dr Jessica Horst，of the University of Sussex's WORD Lab devised an experiment to check how quickly three-year-olds could recognize and（43）___ six new words．The children were visited three times in a week．One group heard the same story three times back-to-back each time and another was read three （44）___ stories．All had the same amount of new words which appeared the same （45）___ of times．

When researchers returned a week later，they found the children who heard the same story over and over had（46）___learned 3.6of the new words．While those（47）___ to a variety of stories remembered only 2.6．They also noted the‘repetition'group learned at a faster rate than those in the‘（48）___'group．

Dr Horst said：‘We are showing that less is more，to a point．And，（49）___，the more times you read to a child and the more books you have will help them．But you don't need to go crazy and buy every single Thomas the Tank Engine book．Reading the same books over and over again helps．'

Speaking of the（50）___ studies，we have found one in three don't read to their children before putting them to bed．Yet 30minutes of one-on-one literacy sessions can improve reading age by nearly two years in less than five months．