Directions:In each of the following groups of words,there are four underlined letters or let-ter combinations marked A,B,C and D.Compare the underlined parts and iden-tdtify the one that is different from the others in pronunciation.Mark your answer by blackening the corresponding letter on the Answer Sheet.
A、pension
B、mission
C、tension
D、revision
(25)__
A、simple
B、beneficial
C、interesting
D、obvious
18.Children don't understand initially what they are reciting, but___it will have an impact on their thinking.