1. She spoke in a very loud voice.

2. She spoke in a very high voice.

3. She spoke in a very low voice.
4. She spoke in a very soft voice.

5. She spoke with a very loud voice.
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Does #1 mean #2? Can we use both #3 and #4? What about #5? Can we use 'with' in place of 'in'?

Voices that are high and low have more to do with where those voices are on the musical scale, not in loudness.

1 and 4 are opposites.

2 and 3 are opposites.

5 is odd, but not necessarily incorrect.

1. "She spoke in a very loud voice" implies that the volume of her voice was high or intense. This does not necessarily mean that she spoke with a high pitch (like in #2), as the terms "loud" and "high" refer to different aspects of speech.

2. In contrast to #1, "She spoke in a very high voice" specifically refers to the pitch of her voice. This means that her voice had a higher tone or frequency compared to the average or expected range of voices.

3. "She spoke in a very low voice" implies that the pitch of her voice was lower than usual. The term "low" in this context refers to the pitch, not the volume.

4. Similarly, "She spoke in a very soft voice" indicates that her voice was not loud or intense. This refers to the volume rather than the pitch of her voice.

5. "She spoke with a very loud voice" is grammatically correct and conveys the same meaning as #1. In this case, the use of "with" instead of "in" indicates that she used a loud voice while speaking. The addition of "with" emphasizes the manner in which she spoke.

In summary, #1 does not mean #2 as they refer to different aspects of speech (volume vs. pitch). Both #3 and #4 can be used, depending on whether you want to emphasize pitch or volume. Lastly, #5 is a correct alternative to #1, using "with" to indicate the manner of speaking.