Done C as well - but not a lot, but enough to maintain C programs and write routines in it.
Worst languages and 4GLs, tried Progress - very restrictive, Visual Basic has a very nasty IDE.
The dbase interactive environments are rubbish compared to the compilers.
Before getting a job I learnt COBOL, BASIC, some XBASE
The non .net versions were kinda hampered by trying to be familiar to users of previous versions, which itself was kinda hampered by the VB for DOS product (actually rather good, but quirky interface).
VB's biggest problem was the mess it got in tryinging to kludge new ideas into a language not really geared to take it - sterling effort by MS, but was never going to be truely achieveable, hence VB.NET being very, very different.
Sadly, I still have to maintain a medium size VB6 app that can't port to .net - and VB6 has just gone out of support. Fortunately, as the runtimes are included in XP and Vista, they continue to get security fixes...
VB 6 - I had edited a lot of the .bas in an external editor, for power reasons, then reloaded and VB screwed all my formatting

.
I ended up rewriting to change all the variable names to the same length.
All the decent xbases short cut on statements (to be faster), pretty sure C does as well, does VB no it doesn't
IF a or b and if a passes still does b ect aghhhhhhhhhhhhhhh!!!!!!!!!!
Really shitty language

When I converted a load of code to produce some data routines it took days!
First time I had changed language and had to change structure of these routines. (Locking control ect, ported all over the place VB was worst) Oh I do like the Clipper dialect!