Structure:(that) + subject + verb

When to use: Use when referring to someone else’s action or describing a specific situation.

Example: She was surprised (that) he forgot her birthday.

NOTE: Optional to omit that in informal contexts.

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Structure: Adjective + to + infinitive

When to use:

1. Use when referring to the subject’s own action or explaining the reason for their feeling.

2. The infinitive verb shows what the subject feels about or intends to do.

Example:

1. She was pleased to receive the invitation.

2. He was relieved to find his wallet.