The number one thing when writing messages of any length in English is to use sentences that make sense and are unambiguous. Look at this message that some non-native speaker of English created.
Native vs Non-native
Whether someone is a native speaker of English or a non-native speaker of English is no excuse for writing gibberish or almost gibberish. Your English has to be correct, not approximately correct because you may end up with ambiguous or confusing nonsense as illustrated above. What can we do with that? Clearly we need to click YES or NO or simply the "x" in the upper right hand corner for fear of what might happen if we press either of the other two options.
The delete option involves more than 20 lines.
The subject is "the delete option" and the verb is "involves". This is a statement. It is giving information.
Are you sure you want to save the deleted text in the Undo buffer?
This is a question. It could be asked more simply, Do you want to save the deleted text that is now in the Undo buffer? OR Do you want to save the deleted text?
Responding No will clear the Undo buffer. This is a statement. The subject is "responding no" and the verb is "will clear". However, the statement is not helping me make a decision as to whether I want to save the deleted text. This additional information is not helping me at all.
Maybe a better message might be, Do you want to undo the deletion? or There are more than 20 lines in the Undo buffer. Do you want to save those lines afterall?
Start with a Bang, not Fluff
And if possible eliminate all the fluff completely. Choose your main point and deliver it in coherent, correct and unambiguous English. When writing a letter or an email a "hello" and a "good-bye" are necessary. When writing a message only the "body" is needed. The body is the meat of the matter. That "body" or the text message via Messenger, Slack or other should be the reason for your writing. And anything following the reason should be any contextual or supplementary information needed for the reader to better handle the question, request, or relayed information just conveyed.
GBEN Complimentary English Assessment
Are you a non-native speaker of English with an intermediate or advanced level of English? Nice! If you need to get better at English now, sign up for a complimentary assessment of your English. The remote appointments takes about an hour. Afterwards you will receive lots of feedback and a proposal. You may decide to hire me or you may opt to simply take full advantage of the feedback and resources. You win no matter what! It is a no-brainer, really.. Here is the link to the scheduling platform for your GBEN Complimentary English Assessment.. Read, select a date, select a start time. Easy!