请问right to left reading order这句话中,read为什么要加-ing.right to lef

请问right to left reading order这句话中,read为什么要加-ing.right to lef 为什么这句话前read要加ing?reading books is a good for 请问"to the right & to the left"是什么意思? right to left的意思 请问这句话中he's＼是什么缩写?还有read的后面为什么要加ing? 为什么要make reading,为什么read要加ing? Read and put the sentences in the right order to make up dia he thinks reading is interesting 为什么read要加ing? I like reading为什么read要加ing He likes reading.这里read为什么要加ing? he likes reading .为什么read要加Ing? right to left 怎么实现的