题干
John ________ play the guitar, but he wants to join the guitar club.
A：can
B：can't
C：does
D：don't
答案(点此获取答案解析）
B
John ________ play the guitar, but he wants to join the guitar club.
A：can
B：can't
C：does
D：don't
殖的生物，其亲子代之间总是存在着一定差异的主要原因是
