"Do you can drive"
A lot of research has shown that there is a sequence in which second language learners acquire structures. In the case above, the learner has reached the stage of realising that questions have a different structure, but is probably generalising that all questions are formed with a verb at the beginning.
"Fish and cheaps"
This is a phonetic error, and most likely results from the student's first language (L1).
For example, French really only has one sound where English has two in the area of /i:/ (as in cheaps) and /I/ (as in chips). This is what's called a minimal pair (a pair of words which differs in only one sound), and French speakers often have problems with this pair.
Confusion with this pair happens with several L1s.