19. A at public universities come from the central region of Thailand B .
A. 1. The students about sixty percent
2. Of the students, about sixty percent
3. About sixty percent of the students
4. Of about sixty percent, the students
B. 1. and from the others the rest 2. and the rest from the others
3. from the rest and the others 4. from the others and the rest
20. A bus A only once a week; B from the outer world.
A. 1. was coming to that small village
2. to that small village was coming
3. came to that small village
4. to that small village comes
B. 1. however, its inhabitants were almost completely cut off
2. moreover, its inhabitants were cut off most completely
3. similarly, its inhabitants were cut off most completely
4. therefore, its inhabitants were almost completely cut off