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This tells us Cambridge is assessing phonic awareness and working memory , not punishing every typo. However, for high-frequency words like "because," "their/there/they're," the scheme is merciless. Those must be correct.
(Point + Evidence, not just Point).
For a 3-mark inference question, the mark scheme explicitly states: Award 1 mark for a valid inference, 1 mark for textual reference (quote or paraphrase), and 1 mark for explanation of how the evidence supports the inference. Do not skip the "because."