1. I like taking walks.

2. I like taking a walk.
(Which one is OK? Are both right?)

3. You should obey the school rules.
4. You should keep the school rules.
5. You should follow the school rules.
(Are all the same?)

6. He helped Mother who was sick in bed.

7. He helped to carry their bags when they were sick.

8. He did his friends' homework when she was sick.

9. He helped his handicapped friend to go to school.

(Would you checke the expressions? )

All are correct except #8. It should be: He did his friend's homework when she was sick.

Using apostrophes for possessives is tricky -- even for native English speakers.

The basic rule is that if the noun ends with s, as friends, then you add the apostrophe after the s to make it possessive. However, in your sentence, you meant the "homework of your friend," so the possessive is "friend's."

3,4,5. Obeying and following are better than keeping. Depending on the context, keeping the rules might indicate that you were thinking of getting rid of the rules but decided to keep them.

I hope this helps a little more. Thanks for asking.

1. Both "I like taking walks" and "I like taking a walk" are correct. The first sentence implies that you enjoy taking walks in general, while the second sentence suggests that you enjoy taking a specific walk.

2. "You should obey the school rules," "You should keep the school rules," and "You should follow the school rules" convey the same general meaning, which is the importance of adhering to the rules set by the school. However, there might be slight differences in emphasis. "Obey the school rules" implies strict compliance without exception, "keep the school rules" suggests maintaining or upholding the rules, and "follow the school rules" denotes adhering to and following the rules in a general sense.

3. Regarding the provided expressions:

- Sentence 6: "He helped Mother who was sick in bed." This sentence conveys that someone helped their mother, who was sick and in bed. The sentence is grammatically correct.

- Sentence 7: "He helped to carry their bags when they were sick." This sentence does not flow grammatically as it combines two unrelated actions in the same sentence. It can be rewritten as "He helped carry their bags when they were sick." This sentence now conveys that someone assisted by carrying their bags when they were sick.

- Sentence 8: "He did his friends' homework when she was sick." In this sentence, the pronouns do not agree. "His friends' homework" indicates that it belongs to multiple friends, while "when she was sick" suggests only one person being sick. This sentence can be corrected to say "He did his friend's homework when she was sick," implying that one friend was sick, and this person helped by completing their homework.

- Sentence 9: "He helped his handicapped friend to go to school." This sentence is grammatically correct and conveys that someone assisted their disabled friend in going to school.