Well, I’ll try my best to help; sorry, I’m still only beginner myself, so maybe it would be wiser to wait for Joel先輩, but I guess it wouldn’t hurt if I try to help in the meantime.
If I’m not mistaken, the rule is this: ため after the present tense verb is the “purpose” ため and ため after past tense verb is the “because” ため。 Knowing this, let’s look at the sentences:
1．「にほんご を べんきょうした ために 。。。」　- the verb 勉強する　（べんきょうする） is in the past tense, so this part translates as “Because I’ve studied Japanese…”
Your answer is 「アニメをみった」. Well, first, I’m afraid, there is a mistake here: the verb 見る　（みる）　is a group 3 verb (even though it looks like a group 1 verb), so the casual past tense would be not みった, but みた。
「にほんご を べんきょうした ために アニメ を みた」　- “Because I’ve studied Japanese, I watched anime”.
Well, seems ok to me. I would have said 「日本語　を　勉強した　ために　アニメ　を　見ること　が　できます」　（にほんご　を　べんきょうした　ために　アニメ　を　みる　こと　が　できます） – “Because I’ve studied Japanese, I’m able to watch anime”, but it contains some season 6 grammar that you haven’t learned yet (assuming you are at the end of the season 5 from which comes this spreadsheet). So, your response seems ok to me, apart from mistaking みる for a group 1 verb.

2. 「TextFugu を かった ために」　- as in the previous sentence, the verb 買う　（かう）　is in the past tense, so we are dealing with the “because” ため again and the first part translates as “Because I’ve bought the TextFugu…”.
Your answer is 「べんきょうしに行った」 – “I went to study”, so the full sentence is “Because I’ve bought the TextFugu, I went to study”. Seems fine to me.

3. 「とうきょう に いった ために」 and again the verb 行く　（いく）　is in the past tense, so – again “because” ため and the first part sentence translates as “Because I’ve gone to Tokyo…”
Your answer is 「きっぷを買いに行った」　- “I went to buy a ticket”. Hm… If it had been the “purpose” ために (in which case the first part would have been 「東京　に　行く　ため　に」　（とうきょう　に　いく　ため　に））, you answer would have made perfect sense – “To go to Tokyo, I went to buy the ticket”. But as it’s the “because” ために… Well, the situation when you have to go buy a ticket, because you’ve been to Tokyo, is not impossible, so I guess your answer is ok, as long as you understand that this is the “because” ために and not the “purpose” ために

4. 「ビール を のんだ ために」　And again the verb 飲む （のむ）　is in the past tense, so – the “because” ため.
“Because I drank beer…”
Your answer is “I didn’t get on the car” (or it might be the train, ship, plane – depends on the context). Seems fine to me, although I would have used 運転しませんでした　（うんてんしませんでした）　- “I didn’t drive”. But your answer seems ok too.

5. 「ビデオ を つくった ために」 Heh, it seems all these five sentences use the “because” ため
Even here, in this last sentence the verb 作る　（つくる）　is in the past tense…
“Because the video was made…”
Your answer “I didn’t see it”. Hm… Sounds a bit strange to me.

Sorry again for not being able to be of more help – it hasn’t been a long time since I’ve finished TextFugu myself, so I’m not much better than you. Still, I hope you find this at least a bit useful.
Anyway, once Joel先輩 gets back he will make everything clear.

• This reply was modified 7 years, 9 months ago by  trunklayer.

Joel wrote:

I can’t seem to find the worksheet in question – what lesson are you up to, specifically?

It’s Season 5, Lesson 6, page 7

Joel wrote:

(For one thing, trunky, みる is group 2 – group 3 consists of just する and くる. Koichi’s description of “group 2 verbs that look like they should be group 1″ makes it SEEM like they’re group 3s, but they’re still all group 2s. Honestly, though, I’ve never been a fan of calling them “group 1″ and “group 2″, because I can never remember which group is which – I learnt them as う-verbs and る-verbs. In Japanese, they’re called 五段 (ごだん) and 一段 (いちだん), for etymological reasons that I don’t precisely recall, but personally I remember because ごだん verbs form the ～た form five different ways, while いちだん verbs only form it one way. But I digress.)

Huge thanks! This has always been a source of a lot of confusion for me, as the jisho.org uses the Japanese names for the groups and TextFugu uses the TextFugu’s names…

• This reply was modified 7 years, 9 months ago by  trunklayer.