In my opinion，not all inventions were invented by ________ accident.—Well，you do seem to have ________ point.Inventing needs much time and hard work.

_____________half an hour earlier,you would have met the famous writer.

How deep is the well—It’s ________.

The number of students from the north ____small.

With Mike _____ as our group leader, we had no trouble finishing the task ahead of time.