Difficulty: Easy
Correct Answer: hearing
Explanation:
Given sentence'We look forward to hear from you.'
Concept/ApproachIn the phrase 'look forward to', the 'to' is a preposition, not the infinitive marker, so it must be followed by a gerund (V+ing): 'to hearing'. This is standard in formal letters.
Step-by-step correctionReplace: 'to hear' → 'to hearing from you'.
Why other options are incorrect'have heard' → wrong tense/aspect and structure.'listen' → wrong verb meaning and form.'No improvement' → keeps a common but nonstandard error.
Final Answerhearing
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