阅读理解，选择正确答案。

      I am Jack. I live near our school. So I can go to school on foot. But sometimes I go by bike. Because it's

so much fun. My father works in our school. We go to school together. On the weekends, I often play with

my friend, Mike. We usually play ping-pong, sometimes we play chess. This weekend, I'm going to visit my

grandparents. Because it's my grandma's birthday.

1. Jack usually goes to school _____________.

A. on foot

B. by bike 

2. Jack's mother lives _____________.

A. in the school

B. near the school

3. Jack goes to school with _____________.

A. his father

B. his friend, Mike

4. Jack and Mike usually _____________.

A. play chess

B. play ping-pong

5. Whose birthday is this weekend?

A. Grandfather's

B. Grandmother's

肌梭感受器的适宜刺激是

A．梭外肌收缩
B．梭外肌松弛
C．梭外肌受牵拉
D．梭内肌紧张性降低
E．梭内肌受压迫