无内胎轮胎近年来应用日益广泛，它没有内胎和垫带，空气直接压入外胎中，其密封性是由外胎和轮辋来保证的。

Suppose a foreign friend of yours has written to inquire about the possibility of making a seven-day visit in China. Write a reply to give him some information. The following should be included:
(1) The place you recommend for him to visit and the reasons ;
(2) The suggested route and the timetable of the visit;
(3) Some advice on how he should prepare for the visit;
(4) Your arrangement for his visit to Beijing.