During this period, although work was very stressful and we also encountered many difficulties, thanks to everyone’s efforts we successfully solved the problems and completed the work smoothly. Thank you all very much for your help!

It was okay. The questions they asked were pretty easy. I was just a little nervous.

Actually, different problems have different solutions.

I see that she always answers the teacher's questions with a smile.

Some problems look hard, but are very simple to do, so you should try doing them.

Money isn't a problem anymore; the main thing is there's no time.

Some problems look simple, but are extremely hard to solve.

Well written, except that the meaning of this sentence is a bit unclear; otherwise, everything else is fine.

Okay, then come to work tomorrow. About this job, do you have any other questions?

However, we must believe: No matter how difficult the problem is, it will be solved.