Answers. I hope you got all of these right.
A stutter makes it difficult to speak. For example, a st-st-st-stutter m-m-makes it d-d-d-d-d-difficult to speak.
At the speech clinic of a university, the lecturer (01) had an idea for helping his stuttering students. He decided to give (02) them some practical exercises. He knew that stuttering is often caused by shyness, (03) so he sent them to shops to ask for things which the shop did not usually have in stock. He told them to ask for the object, then to ask (04) where it could be found, and then (05) how to get there.
One result was a lot of requests for p-p-p-ping-p-p-pong or t-t-t-table t-t-t-t-tennis balls (06) at the university bookshop. At (07) first, the early customers were sent off somewhere (08) else. However, (09) when the fifth student arrived, he found that the bookshop had (10) enough ping-pong balls in stock to supply everyone in the university.
The shop manager was (11) puzzled. He said: "I don't know what's going (12) on. Why should people expect a bookshop to stock ping-pong balls? Well, we have to keep our customers happy. But (13) what really worries me, though, is why everyone who (14) plays ping-pong stutters."