文法

Question 1

ので

Answer 1

because
clause 1 + ので + clause 2

から and だから can be used in a similar fashion, but ので is more commonly used when the reason (clause 1) is impersonal

ex. 天気がいいので出かけよ

Question 2

〜くする

Answer 2

to make something 〜
い adjective + くする

This grammar is used to (deliberately) make something whatever the adjective describes. The い of the adjective is replaced with く, turning it into an adverb.

ex. 赤くする

The verb after く does not necessarily need to be する; it can be other transitive verbs. This grammar is only used with い adjectives.

Question 3

のに (when used with a positive clause)

Answer 3

despite, in spite of, even though
plain form clause + のに

ex. 車があるのにどうして歩くのですか。

Question 4

に (frequency indicator)

Answer 4

frequency indicator
period + に + X number of times

ex. 私達は日に３度食事をします。We have three meals a day.