Makina ang'onoang'ono opangira simenti akhala zida zofunika kwambiri pantchito yomanga, kuwongolera njira yopangira midadada ya konkriti yogwiritsa ntchito zosiyanasiyana. Kuchokera ku nyumba zogona
Palinso mitundu yambiri ya makina a njerwa pamsika, pakati pawo pali makina a njerwa otchedwa konkire block machine. Koma kodi mukudziwa zozindikiritsa makina oyika njerwa? Kodi mukudziwa zomwe zilembo za nambala ya njerwa zimayimira?