1-C. He told me that it was pretty tough at first because he couldn't speak English at all, and he didn't have any friends there.He told me that it was pretty tough at first because he couldn't speak English at all, and he didn't have any friends there.
2-C. I was happy, because I'd worked so hard to make this happen.I was happy, because I'd worked so hard to make this happen.
私は、幸せでした、なぜなら、私は、とても懸命に働いて、これを実現することができたから。
3-C. The results of this experiment were exciting because they suggested a direct connection between reading novels, even for a short time, and the perception of other people's feelings.The results of this experiment were exciting because they suggested a direct connection between reading novels, even for a short time, and the perception of other people's feelings.