描画眉毛时，第一笔应从（）入手
A.头
B.腰
C.峰
D.尾
参考答案：B
There must be a time in every man's life ________.[ ]
A. that he is in low spirits
B. which he is in low spirits
C. when he is in low spirits
D. then he is in low spirits
当事人对保证方式没有约定或约定不明确的，保证责任无法承担，保证合同无效。( )
