单项选择题
A．textured like wood B．colored like wood C．smooth and red D．short and thick
According to the selection more than half of a person's...
单项选择题According to the selection more than half of a person's body is composed of()
A．voluntary muscles B．involuntary muscles C．muscle fibers D．sensory nerves
Muscles are unique fibers, because they can ()A．contrac...
单项选择题Muscles are unique fibers, because they can ()
A．contract B．stretch C．retract D．do all of the above
The writer of the article is()A．Mrs. Whites nieceB．the ...
单项选择题The writer of the article is()
A．Mrs. White's niece B．the Whites' cousin C．Sarah' s friend at college D．Jane' s friend at school
