1. People were worried that their souls might not get back into their bodies.

2. People were worried because their souls might not get back into their bodies.
(Are both the same? Is 'that....' an adverbial phrase?)

3. He was happy that she got the first prize in the speech contest.

4. He was happy because she got the first prize in the speech contest.

(Are both the same?)

5. He was surprised that he heard the news.

6. He was surprised because he heard the news.

7. He was surprised to hear the news.

(Are the three the same?)

1 and 2 mean about the same. They are adverbial clauses, not adverbial phrases.

3 and 4 are about the same.

5 and 6 are about the same. The emphasis in 7 is on the news that he heard -- so it isn't the same as 5 and 6.

1. "People were worried that their souls might not get back into their bodies."

2. "People were worried because their souls might not get back into their bodies."

In these two sentences, both "that" and "because" introduce a subordinate clause that explains the reason for the worry. However, there is a slight difference in emphasis. "That" indicates a direct concern or apprehension about the specific event mentioned, while "because" suggests a causal relationship between the worry and the potential outcome.

3. "He was happy that she got the first prize in the speech contest."

In this sentence, "that" introduces a subordinate clause expressing the reason for the happiness. It indicates that the reason for his happiness is her achievement of winning the first prize in the speech contest.

4. "He was happy because she got the first prize in the speech contest."

This sentence also expresses the reason for his happiness, but the emphasis is on the cause-effect relationship. It suggests that her winning the first prize directly led to his feeling of happiness.

5. "He was surprised that he heard the news."

In this sentence, "that" introduces a subordinate clause explaining the reason for the surprise. It suggests that the reason for his surprise is the fact that he heard the news.

6. "He was surprised because he heard the news."

Similar to the previous example, "because" introduces a subordinate clause explaining the reason for the surprise. It indicates a cause-effect relationship, suggesting that the act of hearing the news directly led to his feeling of surprise.

7. "He was surprised to hear the news."

In this sentence, "to" introduces an infinitive phrase that conveys purpose or intention. It suggests that his surprise was a result of the unexpectedness or significance of hearing the news.

While all three sentences express surprise, there are subtle differences in emphasis. The first two focus on the cause of the surprise, while the third emphasizes the unexpected nature of hearing the news itself.