请从A、B、C中选择合适的答案

When we see teachers, we should stand 　　 .

A. down B. to C. up

Read the text. Choose the right words and write them on the lines.

　　Example：During the holidays my friend Tony sometimes comes to stay with me. We usually play soccer and table tennis together. When we are too (1)________ to do sports, we like to watch videos. My favourite videos (2)________ stories about space. One day, I might go up (3)________ space.

　　Yesterday Tony came to my house again. We played in the garden (4)________ a long time and then we got tired. We also watched a film about castles (5)________ horrible monsters. Tony was scared (6)________ the monsters. So I (7)________ to get another video. It was a film about different kinds of bears which were (8)________ in the cave in a mountain. One day (9)________ was a very big storm. Lots of rocks blocked the cave, so the bears had (10)________ to live. Bears are beautiful animals, but they can be very dangerous too! We enjoyed the film very much and had a lot of fun that day.

Example：coming　　comes　　come

(1)tiring　　　　　　tired　　　free

(2)is　　　　　　　　are　　　　be

(3)over　　　　　　　by　　　into

(4)since　　　　　　for　　　　in

(5)but　　　　　　have　　　with

(6)of　　　　　　　at　　　　to

(7)should　　　　　had　　　have

(8)live　　　　　　lived　　　living

(9)there　　　　　　this　　　it

选择正确答案.