问答题

Section C Conversations
Reading experts have been interested for a long time in discovering what makes reading material difficult. A great deal of (26) has been done on the topic. And now most experts (27) that there are two major (28) in reading difficulty. One is the (29) of the words found in the (30) If they are long, (31) or technical words, the material is more difficult. The other major factor is the (32) of the sentence. (33)
Some experts have developed ways of measuring the readability or difficulty of material. (34) These two factors are effective to measure word difficulty and sentence complexity.
The usualy purpose of measuring difficulty or readability is to be able to provide suitable reading material to children at a certain level. (35) In this way, the material provided can match their reading ability.