My heart was in my mouth as I tried to open the envelope. This means that as I opened the envelope, I was

Step 1: Analyze the question The question tests your knowledge of idioms. The expression is "my heart was in my mouth."

Step 2: Explain the concept The idiom "heart in one's mouth" means feeling very nervous, anxious, or frightened, usually because you are anticipating something that could be bad or dangerous. The image comes from the pounding feeling in your chest when you are scared, as if your heart has jumped up into your throat.

Examples:

• "When the car skidded, my heart was in my mouth." (I was terrified.)
• "She had her heart in her mouth as the results were announced." (She was extremely nervous.)

Step 3: Apply it to the sentence "My heart was in my mouth as I tried to open the envelope." The speaker is nervous about what is inside, perhaps exam results or a letter with important news. The feeling is fear and anxiety about the unknown.

Step 4: Check the options

• A. very happy: no, the idiom does not express joy.
• B. quite eager: you could be eager, but the idiom is about fear and nervousness, not eagerness.
• C. deeply disappointed: disappointment comes after you see bad news, not while you are opening the envelope.
• D. extremely afraid: this is the closest meaning, since it expresses fear and anxiety.

Answer: D. extremely afraid

Tip: For idioms involving body parts, such as "heart in mouth," "cold feet," or "butterflies in the stomach," think about the physical sensation. A heart pounding up into your mouth almost always signals fear or nervousness. Also, be careful with options like "eager" that sound close but do not capture the fear.