(2013·重庆，23)It's not easy to change habits，________ with awareness and self－control，it is possible.
A．for B．or C．but D．so
(2013·新课标Ⅰ，32)There's no way of knowing why one man makes an important discovery________another man，also intelligent，fails.
A．since B．if C．as D．while
(2013·新课标Ⅰ，34)It was a real race________time to get the project done.Luckily，we made it.
A．over B．by C．for D．against
(2013·新课标Ⅱ，11)A serious study of physics is impossible________some knowledge of mathematics.
A．against B．before C．beyond D．without
(2013·北京，26)I have an appointment ________ Dr.Smith, but I need to change it.
A．to B．off C．with D．from
(2013·辽宁，25)________everyone here，I wish you a pleasant journey back to your country.
A．By means of B．On behalf of
C．In search of D．For fear of
