1. He was so excited that he didnt sleep until 2:00 last night.
2. It was late so we had to go back school.
3. She doesn't how to express whenenever having an interview.
4. I can do better if i was given more time.
1. too excited, he didn't go to sleep until 2 o'clock yesterday.
2. It being late, we had no choice but to go back to school.
3. once interviewed, she doesn't know how to express herself.
4. given more time, i will do better than that.
可以先说说啥叫现在分词和过去分词么?