Which form of body language is acceptable almost everywhere?

• A、Shaking hands.

• B、Keeping a short distance.

• C、Kissing on the cheek.

• D、Touching on the shoulder.

What will happen when students depend too much on research tools ?

• A、They won’t make good use of books.

• B、They don’t copy work done by others.

• C、Their studies will be greatly improved.

• D、Their attention to things will last longer.

51.________.