I got confused about hand-written 6, it looks like 4 to me.
And looked up
I'm a Chinese from North coastal part of China mainland, I'd say I didn't notice this problem until I visited the US and read some letters. Unbelievable, I didn't find this during my 6 years stay in Sydney Area, Australia.
Here is my thought: let's start from how to write the 4 and 6.
A 6 written in stroke by myself start with slash / , from upper right, end with a small circle, either end in middle air or touch the slash. The problem I went into was if I wrote too fast I could make the circle too high to close near the starting point, a 6 may look like a 0.
How to write a 4 in my version, a L and then slightly raise up pen, or back to desired cross point then up and down, first practice may left a stroke between - |. *This is the point non-Chinese care, and Chinese not mind.* If one 4 moved the end to left portion, I consider it is bad writing but still a 4 as it have the end out. My problem was, my 4 may look like 9 on upper part so I will try not to enclose.
We write hieroglyphic text, so the characters we use are easily distinguishable from Arabic Numerals.
Now here is the point: 4 in English context hand-writing may not have vertical stroke and horizontal stroke connected on upper-right, this is not a concern to Chinese people.
4 in our thinking, defined by a slash connect to a cross, while the way to draw the cross not matter. We think the any tails stroke out from above, I mean below the horizontal stroke is indicating this character is a 4. As I mentioned above, a 6 to Chinese people, may tail out of left vertical line over horizontal one.
Both sides will get confused, Chinese may connect the right and upper point of the cross but won't press hard the way you writing the 6. I think most people's practice here, won't get confused since 4 is not an option in mind when spot the cross have right top connected. Then here is the common Chinese way of judge below: A is 6; B looks like a 6, but it tip on middle of the horizontal line, not to left, bad writing; C and D and E, some would question why press on connection between right to up on paper, am I right on mind are they something other than 4? If they are 6 why do they have tail cross bottom line?
"Once you cross the line down the bottom, you are no longer 6."
Most Chinese never think of a 6 would have end finished down below, they do ether go up and stop in mid space, or connect to left.
Now I have another question:
May the 6 end in middle space confuse you too?