TAN HONGHUI ANN's answer to Kc's Primary 6 English Singapore question.

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TAN HONGHUI ANN
Tan Honghui Ann's answer
5 answers (Tutor Details)
The answer should be 'had seen'. A past perfect tense would be appropriate when talking about some point in the past (in this case, the decision to buy book) and want to reference an event that happened even earlier (in this case, having watched the movie).

The answer should NOT be 'sees' as it is a past event. AFTER (a certain past event), he DECIDED TO (another past event).