dadas
c
The next two letters are likely C & U. There are at least 2 patterns in these letters. FIrst is the list of vowels that make up every other letter. Then the letters alternate from the ends of the alphabet. If there is a Z, a B, then a Y, then C would likely be next, and then X. But there would be whatever vowel in sequence next.
I,V
B (Black). Order of snooker balls.
bb
The next letter in sequence a, l, b, e, m, f, i, n, j is the letter m. Why? The easiest way to figure this one out is to assign a number to each letter, beginning with 'A' =1. Therefore we have 1, 12, 2, 5, 13, 6, 9, 14, and 10. Next, look for a pattern in the series of numbers. Although not too obvious, start with the first letter 'A', then skip the next two letters 'L' and 'B'. 'E' is the next letter, which is 'A' plus 4. Then skip two letters 'M' and 'F' and add 4 to get 'I' ('E' + 4). This seems to be a good pattern. Continuing on the second letter in the sequence 'L', skip two letters. The next letter is 'M' which is 'L' plus 1. Then skip two letters and add 1, which is 'N'. So far we have a good pattern established. Finally, let's look at the third letter 'B'. Skip both letters 'E' and 'M' and we find the letter 'F', which is 'B' plus 4. Then add 4 to 'F', and we find the letter 'M' after jumping the two letters 'I' and 'N'. So the pattern is add 4 to the first letter, skip two letters, and you have the fourth letter. Then add 1 to the second letter, skip two letters, and you have the fifth. Add 4 to the third letter, and you have the sixth. The pattern then repeats itself. Since 4 was added to 'A', then added to 'E', then added to 'I', the next letter is 'M' ('I' + 4). Continuing on, the next two letters would be 'O' and 'N'. Hope this makes it a little clearer.
"a" & "b".
bb
bb
B
Check out the link for the sequence.
the next letter would be 'b'