There are two “te” forms, and a “ta” form, which is usually conjugates pretty much identically to the “te” form. This gives no information on how the verb conjugates into the “masu” form.
I know WK is a site for learning vocab, and not grammar, but I still think it would be a lot more useful if there was at least one “te” form and one “masu” form example sentence for each vocab word. With this, in addition to the dictionary form that you are actually tested on, it would be possible to know how the verb conjugates in pretty much every situation.
I also realize that WK tells you things like the verb being a “godan” verb, but unless you’ve already studied Japanese grammar, such a description is pretty meaningless. (I’ve also never seen the term “godan verb” in any of the beginner Japanese grammar resources I’ve used.)
So, yeah. That’s my suggestion. More conjugation forms = better.
Considering that most words on the site only have one example sentence to begin with, you can email them the suggestion if you want, but I’m not sure when they’ll get around to adding another batch of example sentences.
The third sentence for levels 1-10 was added a few months ago. Before, levels 1-10 only had 2 each. Everything from level 11 and on has 1 (at least I’m fairly sure of that).
If you just want a simple way of quickly knowing how to get the masu form for any verb, just find out wether they are Ru-verbs or U-verbs.
If the verb ends in る with an え or い sound before it, it is probably a Ru-verb, and you only need to take away the る and add ます.
For example:
食べるー>食べます
調べるー>調べます
着るー>着ます
U-verbs are mostly everything else. You need to take the last kana with an う sound, and change it to an い sound, then add ます.
For example:
死ぬー>死にます
笑うー>笑います
持つー>持ちます
回るー>回ります
Besides this, there’s two special cases: するー>します and くるー>きます.