I've only been waiting for an hour.

我已经等了一个小时了。

I'm sorry to have kept you waiting.

很抱歉，让你久等了。[分词作状语]

I feel the same way.

我有同感。

My father had an interview with the principal to discuss my work.

我父亲会见校长讨论我的功课情况。

The staff in this shop is very helpful.

这家商店的店员很热心。

If you concentrate all your energies on the study of English, you will master the language.

你若全力以赴地学习英语，你会掌握这门语言的。