The teacher is busy ____ teaching.
In ________ distance is a tall tree which is said to have ________ history of over 500 years.
Believe it or not , that is _____ people call the sixth sense.
What I want to know is ____ he likes the gift given by us.
I like _____ in the autumn when the weather is clear and bright.
----Could I use your computer for a few moments, please? -----______.I’m not using it myself.