1. When you call to others, use the home phone.
2. Call to others' home phone numbers.
3. With the home phone, call to others' home phones. Don't use cell phone when you call others' cell phones. Use the Interphone. It's much cheaper.
(Are the expressions grammatical?)
Remove "to" from before "others." Simply "call others..." is fine.
All three expressions are grammatically correct. However, there are some stylistic variations that could be improved.
1. "When you call others, use the home phone." This sentence is grammatically correct, but it could be more specific. Who are "others"? Is there a particular reason why you should use the home phone? Adding more context or details could make the sentence clearer.
2. "Call to others' home phone numbers." This sentence is grammatically correct, but it could be phrased more naturally. Instead, you could say, "Call others using their home phone numbers." This phrasing makes it clear that you are using their home phone numbers to make the call.
3. "With the home phone, call to others' home phones. Don't use cell phone when you call others' cell phones. Use the Interphone. It's much cheaper." This passage is grammatically correct, but it could be improved for clarity and conciseness. Here's a revised version: "When calling others, use a home phone to contact their home phones. Avoid using cell phones to call other cell phones. Instead, consider using an interphone, as it is a more cost-effective option."
Remember, correct grammar is essential for clear communication, but it's also important to consider the context and clarity of your message.