One-letter word at the end of line of text [closed]

In English language, is a one-letter word (such as I or a) allowed to be at the end of line? (This question is about a single-letter word within a sentence, placed just before a linebreak.)

For example, is this allowed?

It was a sunny day yesterday, so I
took a sunbath.

In the example, I is at the end of a line of text, just before a linebreak.

Yes. There is nothing to prevent a single-letter word like I or a from being on its own at the end of a line. Sometimes a text just happens to fall that way.

However, it's bad form in English to split a word in such a way that a single letter ends the line a- lone, with a hyphen.

The Wikipedia article on syllabification provides a clue:

For example, it is not possible to syllabify "learning" as lear-ning according to the correct syllabification of the living language. Seeing only lear- at the end of a line might mislead the reader into pronouncing the word incorrectly, as the digraph ea can hold many different values. The history of English orthography accounts for such phenomena.

Leaving just a single letter on the end of a line, like alone above, slows down the reading more than forcing the whole word on to the next line (perhaps by widening the space between words if the text is fully justified).

I don't know if my contrived text will work on your system, so here's what it should look like:

Yes, one-letter word is allowed to be at the end of line.