～かというと

A question word + かというと can literally be read as "if I were to tell you who/what/when/etc." Its intent is to emphasize the information that follows, or to purposefully delay providing that information to create suspense or dramatic effect.

どちらかというと is a set phrase that means "if anything" or "if I have to decide." A "why" word like どうして or なぜ + かというと is used to mean "because" or "the reason is." Other question words with this phrase can be read as "to tell you who/what/when..."

スミスさんは、日本語が上手だ。なぜかというと、日本に長く住んでいたからだ。
Smith-san's Japanese is good. The reason is that he lived in Japan for a long time.

私は辛い食べ物が好きだから、どちらかというと日本料理より、韓国料理の方が好きだ。
I like spicy foods, so if I had to decide, I like Korean food more than Japanese food.

A: 今度のミーティングはいつですか。
B: えっと、今度のミーティングはいつかというと、あっ、来週の水曜日ですね。
A: When is the next meeting?
B: Er, to tell you when the next meeting is, ah, it's next Wednesday.

このコンピュータのメモリは、どのぐらいかというと、2GBぐらいです。
As for this computer's memory, to tell you how much it has, it's about 2 GB.

に対して 2.0

A noun + に対して can be used to describe something towards, for, or with regard to that noun. When used to modify other nouns, the form に対する is used instead.

日本語では、目上の人に対して「あなた」と呼ぶのはとても失礼なことだ。
In Japanese, calling someone who's your superior "anata" is very rude.

税金を払うことは、国民の国に対する義務である。
Paying taxes is the citizens' duty towards their country.

日本語を勉強して、日本の歴史に対する興味がさらに強くなった。
In studying Japanese, my interest for Japanese history became even stronger.

日本語や中国語を勉強して、アジアの国々に対する見方が変わった。
In studying Japanese and Chinese, my perspective towards Asian countries changed.

それなら

Beginning a sentence with それなら provides a meaning of "if so", "then", or "if that's the case." It references a previous statement and usually goes on to provide some sort of response on it.

A: 今夜、どこかおいしいレストランで食事したいと思っているんだけど。
B: ああ、それなら、新しくできた和食レストランに行ってみたら？なかなかおいしかった。
A: Tonight I think I want to eat at a good restaurant...
B: Ah, then why don't you try going to the new Japanese restaurant? They were pretty tasty.

それなら、リーさんは指輪を買って、アリスにあげたほうがいいね。
If that's the case, Lee-san should buy the ring and give it to Alice.

両親は毎日のように、よく勉強していい大学に入りなさいといいます。それなら、私が勉強している時、弟や妹に静かにするように言ってほしいと思います。
Almost every day my parents tell me to study well to get into a good university. If that's the case, I think I want to tell my little brother and sister to be quiet whenever I'm studying.

それなら全て捨てていきたい。
If so, I want to through everything away. (from Ayato's lovely "Addicted" song)

Non-Past Verb + ことはない

A non-past verb plus ことはない can be used to express "don't have to", "don't need to", or "there's no need to..." The は may be dropped in casual conversation.

次の電車がすぐ来るから、急ぐことはありません。ゆっくり行きましょう。
The next train will come soon, so there's no need to rush. Let's take our time.

アルフォンゾは舌がないから、恐れることないんだ。
Alfonzo doesn't have a tongue, so there's no need to be afraid.

インターネットで注文すればいいから、店まで買いに行くことはないよ。
Since you can order things on the internet, you don't have to go to the store to shop anymore.

金持ちのようになってたから、お金に心配することはなんだよ。
Since we've gotten to the point where we're rich, we don't have to worry about money.

だが

Beginning a statement with the simple だが can show that the previous sentence and the current sentence have contrasting or opposing ideas. It's generally used in written language and reads as "but" or "however."

私は日本文学を研究したいと思っている。だが、両親は私に医者になってほしがっている。
I've been thinking that I want to research Japanese literature. But, my parents want me to become a doctor.

リーさんは毎日消防士になりたいと言っていました。だが、今日は、大統領になりたいと言っています。
Every day, Lee-san said that he wanted to become a firefighter. However, today he's saying that he wants to become president.

Wikipediaは何かを調べる時にとても便利だ。だが、間違った情報もたくさんあるので、注意した方がいい。
Wikipedia is very convenient when investigating something. However, it also has a lot of incorrect information, so you'd better be careful there.

電車にかばんを忘れてしまったと思っていました。だが、彼氏はベッドの下に見つけました。
I thought I forgot my bag on the train. But my boyfriend found it under the bed.

～ことに

A noun, adjective, or verb + ことに can be used to express the speaker's feelings about what is said in the next part of the sentence. It's limited to a certain set of words and is translated as something like "it is X that..." as in "it is sad that..." or "I am X that..." as in "I am happy that..." A couple verb examples from Tobira are 驚いたことに (to one's surprise) and 腹の立つことに (what makes me angry is that...)

悲しいことに、大学を卒業してから、大学時代の友達と会えなくなってしまった。
I'm sad that once I graduate university, I won't be able to see any of my university friends anymore.

嬉しいことに、シュウは学校のあとに家にくるって言ってた。
I'm happy that Shuu said he'll come over to my house after school.

残念なことに、私達のチームは最後の試合で負けてしまった。
To my regret, our team lost at the end of the match.

驚いたことに、カナトはお菓子を食べないで寝るんだよ。
To my surprise, Kanato went to bed without eating any sweets.

上に

The word 上に can be used to introduce additional information in a sentence, providing greater emphasis than something like それに. It can be read as "in addition to...", "besides", "not only... but also...", or "as well."

最近の子供は、外で遊ばない上に本も読まないらしい。
It seems like not only do kids these days not play outside, but they also don't read books.

リーさんはよく歌える上にギターを引けて、かっこいいね。
Not only can Lee-san sing well, but he can also play the guitar - he's so cool.

このクラスは毎月試験がある上に宿題もたくさんあるから、とても大変だ。
This class has a lot of homework in addition to tests every month, so it's really tough.

スバル君は血を吸うのが好きな上にピアノを引くのが好きだよ。
Subaru-kun likes sucking blood, and he likes playing the piano as well.